Abstract
This cuDNN Developer Guide provides an overview of cuDNN 7.4.2, and details about the types, enums, and routines within the cuDNN library API.
For previously released cuDNN developer documentation, see cuDNN Archives.
NVIDIA^{®} cuDNN is a GPUaccelerated library of primitives for deep neural networks. It provides highly tuned implementations of routines arising frequently in DNN applications:
 Convolution forward and backward, including crosscorrelation
 Pooling forward and backward
 Softmax forward and backward
 Neuron activations forward and backward:
 Rectified linear (ReLU)
 Sigmoid
 Hyperbolic tangent (TANH)
 Tensor transformation functions
 LRN, LCN and batch normalization forward and backward
cuDNN's convolution routines aim for a performance that is competitive with the fastest GEMM (matrix multiply)based implementations of such routines, while using significantly less memory.
cuDNN features include customizable data layouts, supporting flexible dimension ordering, striding, and subregions for the 4D tensors used as inputs and outputs to all of its routines. This flexibility allows easy integration into any neural network implementation, and avoids the input/output transposition steps sometimes necessary with GEMMbased convolutions.
cuDNN offers a contextbased API that allows for easy multithreading and (optional) interoperability with CUDA streams.
Basic concepts are described in this section.
2.1. Programming Model
The cuDNN Library exposes a Host API but assumes that for operations using the GPU, the necessary data is directly accessible from the device.
An application using cuDNN must initialize a handle to the library context by calling cudnnCreate()
. This handle is explicitly passed to every subsequent library function that operates on GPU data. Once the application finishes using cuDNN, it can release the resources associated with the library handle using cudnnDestroy()
. This approach allows the user to explicitly control the library's functioning when using multiple host threads, GPUs and CUDA Streams.
For example, an application can use cudaSetDevice()
to associate different devices with different host threads, and in each of those host threads, use a unique cuDNN handle that directs the library calls to the device associated with it. Thus the cuDNN library calls made with different handles will automatically run on different devices.
The device associated with a particular cuDNN context is assumed to remain unchanged between the corresponding cudnnCreate()
and cudnnDestroy()
calls. In order for the cuDNN library to use a different device within the same host thread, the application must set the new device to be used by calling cudaSetDevice()
and then create another cuDNN context, which will be associated with the new device, by calling cudnnCreate()
.
cuDNN API Compatibility
Beginning in cuDNN 7, the binary compatibility of patch and minor releases is maintained as follows:
 Any patch release x.y.z is forward or backwardcompatible with applications built against another cuDNN patch release x.y.w (i.e., of the same major and minor version number, but having w!=z)
 cuDNN minor releases beginning with cuDNN 7 are binary backwardcompatible with applications built against the same or earlier patch release (i.e., an app built against cuDNN 7.x is binary compatible with cuDNN library 7.y, where y>=x)
 Applications compiled with a cuDNN version 7.y are not guaranteed to work with 7.x release when y > x.
2.2. Convolution Formulas
This section describes the various convolution formulas implemented in cuDNN convolution functions.
The convolution terms described in the table below apply to all the convolution formulas that follow.
Term  Description 

$x$  Input (image) Tensor 
$w$  Weight Tensor 
$y$  Output Tensor 
$n$  Current Batch Size 
$c$  Current Input Channel 
$C$  Total Input Channels 
$H$  Input Image Height 
$W$  Input Image Width 
$k$  Current Output Channel 
$K$  Total Output Channels 
$p$  Current Output Height Position 
$q$  Current Output Width Position 
$G$  Group Count 
$\mathit{pad}$  Padding Value 
$u$  Vertical Subsample Stride (along Height) 
$\mathit{v}$  Horizontal Subsample Stride (along Width) 
${\mathit{dil}}_{\mathit{h}}$  Vertical Dilation (along Height) 
${\mathit{dil}}_{\mathit{w}}$  Horizontal Dilation (along Width) 
$r$  Current Filter Height 
$R$  Total Filter Height 
$s$  Current Filter Width 
$S$  Total Filter Width 
${C}_{g}$  $\frac{C}{G}$ 
${K}_{g}$  $\frac{K}{G}$ 
Normal Convolution (using crosscorrelation mode)
${y}_{\mathit{n,\; k,\; p,\; q}}=\underset{c}{\overset{C}{\sum}}\phantom{\rule{5px}{0ex}}\underset{r}{\overset{R}{\sum}}\phantom{\rule{5px}{0ex}}\underset{s}{\overset{S}{\sum}}\phantom{\rule{10px}{0ex}}{x}_{\mathit{n,\; c,\; p+r,\; q+s}}\phantom{\rule{15px}{0ex}}\times \phantom{\rule{15px}{0ex}}{w}_{\mathit{k,c,r,s}}$
Convolution with Padding
${x}_{\mathit{<0,\; <0}}\phantom{\rule{5px}{0ex}}=0$
${x}_{\mathit{>H,\; >W}}\phantom{\rule{5px}{0ex}}=0$
${y}_{\mathit{n,\; k,\; p,\; q}}=\underset{c}{\overset{C}{\sum}}\phantom{\rule{5px}{0ex}}\underset{r}{\overset{R}{\sum}}\phantom{\rule{5px}{0ex}}\underset{s}{\overset{S}{\sum}}\phantom{\rule{10px}{0ex}}{x}_{\mathit{n,\; c,\; p+rpad,\; q+spad}}\phantom{\rule{15px}{0ex}}\times \phantom{\rule{15px}{0ex}}{w}_{\mathit{k,c,r,s}}$
Convolution with SubsampleStriding
${y}_{\mathit{n,\; k,\; p,\; q}}=\underset{c}{\overset{C}{\sum}}\phantom{\rule{5px}{0ex}}\underset{r}{\overset{R}{\sum}}\phantom{\rule{5px}{0ex}}\underset{s}{\overset{S}{\sum}}\phantom{\rule{10px}{0ex}}{x}_{\mathit{n,\; c,\; (p*u)\; +\; r,\; (q*v)\; +\; s}}\phantom{\rule{15px}{0ex}}\times \phantom{\rule{15px}{0ex}}{w}_{\mathit{k,c,r,s}}$
Convolution with Dilation
${y}_{\mathit{n,\; k,\; p,\; q}}=\underset{c}{\overset{C}{\sum}}\phantom{\rule{5px}{0ex}}\underset{r}{\overset{R}{\sum}}\phantom{\rule{5px}{0ex}}\underset{s}{\overset{S}{\sum}}\phantom{\rule{10px}{0ex}}{x}_{\mathit{n,\; c,\; p\; +\; (r*dilh),\; q\; +\; (s*dilw)}}\phantom{\rule{15px}{0ex}}\times \phantom{\rule{15px}{0ex}}{w}_{\mathit{k,c,r,s}}$
Convolution using Convolution Mode
${y}_{\mathit{n,\; k,\; p,\; q}}=\underset{c}{\overset{C}{\sum}}\phantom{\rule{5px}{0ex}}\underset{r}{\overset{R}{\sum}}\phantom{\rule{5px}{0ex}}\underset{s}{\overset{S}{\sum}}\phantom{\rule{10px}{0ex}}{x}_{\mathit{n,\; c,\; p\; +\; r,\; q\; +\; s}}\phantom{\rule{15px}{0ex}}\times \phantom{\rule{15px}{0ex}}{w}_{\mathit{k,\; c,\; Rr1,\; Ss1}}$
Convolution using Grouped Convolution
${C}_{g}=\frac{C}{G}$
${K}_{g}=\frac{K}{G}$
${y}_{\mathit{n,\; k,\; p,\; q}}=\underset{c}{\overset{{C}_{g}}{\sum}}\phantom{\rule{5px}{0ex}}\underset{r}{\overset{R}{\sum}}\phantom{\rule{5px}{0ex}}\underset{s}{\overset{S}{\sum}}\phantom{\rule{10px}{0ex}}{x}_{\mathit{n,\; Cg*floor(k/Kg)+c,\; p+r,\; q+s}}\phantom{\rule{15px}{0ex}}\times \phantom{\rule{15px}{0ex}}{w}_{\mathit{k,c,r,s}}$
2.3. Notation
As of CUDNN v4 we have adopted a mathematicalyinspired notation for layer inputs and outputs using x,y,dx,dy,b,w
for common layer parameters. This was done to improve the readability and ease of understanding of the meaning of the parameters. All layers now follow a uniform convention as below:
During Inference:
y = layerFunction(x, otherParams)
.
During backpropagation:
(dx, dOtherParams) = layerFunctionGradient(x,y,dy,otherParams)
For convolution the notation is
y = x*w+b
where w
is the matrix of filter weights, x
is the previous layer's data (during inference), y
is the next layer's data, b
is the bias and *
is the convolution operator.
In backpropagation routines the parameters keep their meanings.
The parameters dx,dy,dw,db
always refer to the gradient of the final network error function with respect to a given parameter. So dy
in all backpropagation routines always refers to error gradient backpropagated through the network computation graph so far. Similarly other parameters in more specialized layers, such as, for instance, dMeans
or dBnBias
refer to gradients of the loss function wrt those parameters.
w
is used in the API for both the width of the x
tensor and convolution filter matrix. To resolve this ambiguity we use w
and filter
notation interchangeably for convolution filter weight matrix. The meaning is clear from the context since the layer width is always referenced near its height.
2.4. Tensor Descriptor
The cuDNN Library describes data holding images, videos and any other data with contents with a generic nD tensor defined with the following parameters :
 a dimension
nbDims
from 3 to 8  a data type (32bit floating point, 64 bitfloating point, 16 bit floating point...)
dimA
integer array defining the size of each dimensionstrideA
integer array defining the stride of each dimension (e.g the number of elements to add to reach the next element from the same dimension)
The first dimension of the tensor defines the batch size n
, and the second dimension defines the number of features maps c
. This tensor definition allows for example to have some dimensions overlapping each others within the same tensor by having the stride of one dimension smaller than the product of the dimension and the stride of the next dimension. In cuDNN, unless specified otherwise, all routines will support tensors with overlapping dimensions for forward pass input tensors, however, dimensions of the output tensors cannot overlap. Even though this tensor format supports negative strides (which can be useful for data mirroring), cuDNN routines do not support tensors with negative strides unless specified otherwise.
2.4.1. WXYZ Tensor Descriptor
Tensor descriptor formats are identified using acronyms, with each letter referencing a corresponding dimension. In this document, the usage of this terminology implies :
 all the strides are strictly positive
 the dimensions referenced by the letters are sorted in decreasing order of their respective strides
2.4.2. 4D Tensor Descriptor
A 4D Tensor descriptor is used to define the format for batches of 2D images with 4 letters : N,C,H,W for respectively the batch size, the number of feature maps, the height and the width. The letters are sorted in decreasing order of the strides. The commonly used 4D tensor formats are :
 NCHW
 NHWC
 CHWN
2.4.3. 5D Tensor Description
A 5D Tensor descriptor is used to define the format of batch of 3D images with 5 letters : N,C,D,H,W for respectively the batch size, the number of feature maps, the depth, the height and the width. The letters are sorted in descreasing order of the strides. The commonly used 5D tensor formats are called :
 NCDHW
 NDHWC
 CDHWN
2.4.4. Fullypacked tensors
A tensor is defined as XYZfullypacked
if and only if :
 the number of tensor dimensions is equal to the number of letters preceding the
fullypacked
suffix.  the stride of the ith dimension is equal to the product of the (i+1)th dimension by the (i+1)th stride.
 the stride of the last dimension is 1.
2.4.5. Partiallypacked tensors
The partially 'XYZpacked' terminology only applies in a context of a tensor format described with a superset of the letters used to define a partiallypacked tensor. A WXYZ tensor is defined as XYZpacked
if and only if :
 the strides of all dimensions NOT referenced in the packed suffix are greater or equal to the product of the next dimension by the next stride.
 the stride of each dimension referenced in the packed suffix in position i is equal to the product of the (i+1)st dimension by the (i+1)st stride.
 if last tensor's dimension is present in the packed suffix, its stride is 1.
For example a NHWC tensor WCpacked means that the c_stride is equal to 1 and w_stride is equal to c_dim x c_stride. In practice, the packed suffix is usually with slowest changing dimensions of a tensor but it is also possible to refer to a NCHW tensor that is only Npacked.
2.4.6. Spatially packed tensors
Spatiallypacked tensors are defined as partiallypacked in spatial dimensions.
For example a spatiallypacked 4D tensor would mean that the tensor is either NCHW HWpacked or CNHW HWpacked.
2.4.7. Overlapping tensors
A tensor is defined to be overlapping if a iterating over a full range of dimensions produces the same address more than once.
In practice an overlapped tensor will have stride[i1] < stride[i]*dim[i] for some of the i from [1,nbDims] interval.
2.5. Thread Safety
The library is thread safe and its functions can be called from multiple host threads, as long as threads to do not share the same cuDNN handle simultaneously.
2.6. Reproducibility (determinism)
By design, most of cuDNN's routines from a given version generate the same bitwise results across runs when executed on GPUs with the same architecture and the same number of SMs. However, bitwise reproducibility is not guaranteed across versions, as the implementation of a given routine may change. With the current release, the following routines do not guarantee reproducibility because they use atomic operations:
cudnnConvolutionBackwardFilter
whenCUDNN_CONVOLUTION_BWD_FILTER_ALGO_0
orCUDNN_CONVOLUTION_BWD_FILTER_ALGO_3
is usedcudnnConvolutionBackwardData
whenCUDNN_CONVOLUTION_BWD_DATA_ALGO_0
is usedcudnnPoolingBackward
whenCUDNN_POOLING_MAX
is usedcudnnSpatialTfSamplerBackward
2.7. Scaling Parameters
Many cuDNN routines like cudnnConvolutionForward accept pointers in host memory to scaling factors alpha
and beta
. These scaling factors are used to blend the computed values with the prior values in the destination tensor as follows (see Figure 1):
dstValue = alpha*computedValue + beta*priorDstValue.
The dstValue
is written to after being read.
Figure 1. Scaling Parameters for Convolution
When beta
is zero, the output is not read and may contain uninitialized data (including NaN).
These parameters are passed using a host memory pointer. The storage data types for alpha
and beta
are:

float
for HALF and FLOAT tensors, and 
double
for DOUBLE tensors.
For improved performance use beta
= 0.0. Use a nonzero value for beta only when you need to blend the current output tensor values with the prior values of the output tensor.
Type Conversion
When the data input x
, the filter input w
and the output y
are all in INT8 data type, the function cudnnConvolutionBiasActivationForward()
will perform the type conversion as shown in Figure 2:
Accumulators are 32bit integers which wrap on overflow.
Figure 2. INT8 for cudnnConvolutionBiasActivationForward
2.8. Tensor Core Operations
cuDNN v7 introduced the acceleration of compute intensive routines using Tensor Core hardware on supported GPU SM versions. Tensor Core acceleration (using Tensor Core Operations) can be exploited by the library user via the cudnnMathType_t enumerator. This enumerator specifies the available options for Tensor Core enablement and is expected to be applied on a perroutine basis.
Kernels using Tensor Core Operations for are available for both Convolutions and RNNs.
Tensor Core Operations for Convolution Functions
The below Convolution functions can be run as Tensor Core operations:
Tensor Core Operations kernels will be triggered in these paths only when:
 cudnnSetConvolutionMathType is called on the appropriate convolution descriptor setting
mathType
to CUDNN_TENSOR_OP_MATH. cudnnConvolutionForward
is called using algo = CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_PRECOMP_GEMM or CUDNN_CONVOLUTION_FWD_ALGO_WINOGRAD_NONFUSEDcudnnConvolutionBackwardData
using algo = CUDNN_CONVOLUTION_BWD_DATA_ALGO_1 or CUDNN_CONVOLUTION_BWD_DATA_ALGO_WINOGRAD_NONFUSED, andcudnnConvolutionBackwardFilter
using algo = CUDNN_CONVOLUTION_BWD_FILTER_ALGO_1 or CUDNN_CONVOLUTION_BWD_FILTER_ALGO_WINOGRAD_NONFUSED
For algorithms other than *_ALGO_WINOGRAD_NONFUSED, the following are a few requirements to run Tensor Core operations:
 Input, Filter and Output descriptors (
xDesc, yDesc, wDesc, dxDesc, dyDesc
anddwDesc
as applicable) havedataType
= CUDNN_DATA_HALF.  The number of Input and Output feature maps is a multiple of 8.
 The Filter is of type CUDNN_TENSOR_NCHW or CUDNN_TENSOR_NHWC. When using a filter of type CUDNN_TENSOR_NHWC, Input, Filter and Output data pointers (X, Y, W, dX, dY, and dW as applicable) need to be aligned to 128 bit boundaries.
Tensor Core Operations for RNN Functions
 cudnnRNNForwardInference
 cudnnRNNForwardTraining
 cudnnRNNBackwardData
 cudnnRNNBackwardWeights
 cudnnRNNForwardInferenceEx
 cudnnRNNForwardTrainingEx
 cudnnRNNBackwardDataEx
 cudnnRNNBackwardWeightsEx
Tensor Core Operations kernels will be triggered in these paths only when:
 cudnnSetRNNMatrixMathType is called on the appropriate RNN descriptor setting
mathType
to CUDNN_TENSOR_OP_MATH.  All routines are called using algo = CUDNN_RNN_ALGO_STANDARD or CUDNN_RNN_ALGO_PERSIST_STATIC. (new for 7.1)
 For algo = CUDNN_RNN_ALGO_STANDARD, Hidden State size, Input size and Batch size are all multiples of 8. (new for 7.1)
 For algo = CUDNN_RNN_ALGO_PERSIST_STATIC, Hidden State size and Input size are multiples of 32, Batch size is a multiple of 8. If Batch size exceeds 96 (forward training or inference) or 32 (backward data), Batch sizes constraints may be stricter and large poweroftwo Batch sizes may be needed. (new for 7.1)
See also Features of RNN Functions.
For all cases, the CUDNN_TENSOR_OP_MATH enumerator is an indicator that the use of Tensor Cores is permissible, but not required. cuDNN may prefer not to use Tensor Core Operations (for instance, when the problem size is not suited to Tensor Core acceleration), and instead use an alternative implementation based on regular floating point operations.
2.8.1. Tensor Core Operations Notes
Some notes on Tensor Core Operations use in cuDNN v7 on sm_70:
Tensor Core operations are supported on the Volta GPU family, those operations perform parallel floating point accumulation of multiple floating point products. Setting the math mode to CUDNN_TENSOR_OP_MATH indicates that the library will use Tensor Core operations as mentioned previously. The default is CUDNN_DEFAULT_MATH, this default indicates that the Tensor Core operations will be avoided by the library. The default mode is a serialized operation, the Tensor Core operations are parallelized operation, thus the two might result in slight different numerical results due to the different sequencing of operations. Note: The library falls back to the default math mode when Tensor Core operations are not supported or not permitted.
The result of multiplying two matrices using Tensor Core Operations is very close, but not always identical, to the product achieved using some sequence of legacy scalar floating point operations. So cuDNN requires explicit user optin before enabling the use of Tensor Core Operations. However, experiments training common Deep Learning models show negligible difference between using Tensor Core Operations and legacy floating point paths as measured by both final network accuracy and iteration count to convergence. Consequently, the library treats both modes of operation as functionally indistinguishable, and allows for the legacy paths to serve as legitimate fallbacks for cases in which the use of Tensor Core Operations is unsuitable.
2.8.2. Tensor Operations Speedup Tips
Some tips on Reducing Computation Time for Tensor Core Operations:
 The computation time for FP32 tensors can be reduced by selecting CUDNN_TENSOR_OP_MATH_ALLOW_CONVERSION enum value for
cudnnMathType_t
. In this mode the FP32 tensors are internally downconverted to FP16, the tensor op math is performed, and finally upconverted to FP32 as outputs.  When the input channel size
c
is a multiple of 32, you can use the new data type CUDNN_DATA_INT8x32 to accelerate your convolution computation. If you are already using INT8, which is INT8x4, then to use the new INT8x32, ensure that your data is such that the input channel sizec
is a multiple of 32, instead of a multiple of 4, as you would have had it for INT8x4. The new CUDNN_DATA_INT8x32 data type defines the data as 32element vectors, each element being 8bit signed integer.Note:This data type is only supported with the tensor format CUDNN_TENSOR_NCHW_VECT_C. See the description for cudnnDataType_t.
Note:This new data type can only be used with CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_PRECOMP_GEMM. See cudnnConvolutionFwdAlgo_t.
Note:Note that this CUDNN_DATA_INT8x32 is only supported by sm_72.
2.9. GPU and driver requirements
cuDNN v7.0 supports NVIDIA GPUs of compute capability 3.0 and higher. For x86_64 platform, cuDNN v7.0 comes with two deliverables: one requires a NVIDIA Driver compatible with CUDA Toolkit 8.0, the other requires a NVIDIA Driver compatible with CUDA Toolkit 9.0.
If you are using cuDNN with a Volta GPU, version 7 or later is required.
2.10. Backward compatibility and deprecation policy
When changing the API of an existing cuDNN function "foo" (usually to support some new functionality), first, a new routine "foo_v<n>
" is created where n
represents the cuDNN version where the new API is first introduced, leaving "foo" untouched. This ensures backward compatibility with the version n1
of cuDNN. At this point, "foo" is considered deprecated, and should be treated as such by users of cuDNN. We gradually eliminate deprecated and suffixed API entries over the course of a few releases of the library per the following policy:
 In release
n+1
, the legacy API entry "foo" is remapped to a new API "foo_v<f>
" wheref
is some cuDNN version anterior ton
.  Also in release
n+1
, the unsuffixed API entry "foo" is modified to have the same signature as "foo_<n>
". "foo_<n>
" is retained asis.  The deprecated former API entry with an anterior suffix _v
<f>
and new API entry with suffix _v<n>
are maintained in this release.  In release
n+2
, both suffixed entries of a given entry are removed.
As a rule of thumb, when a routine appears in two forms, one with a suffix and one with no suffix, the nonsuffixed entry is to be treated as deprecated. In this case, it is strongly advised that users migrate to the new suffixed API entry to guarantee backwards compatibility in the following cuDNN release. When a routine appears with multiple suffixes, the unsuffixed API entry is mapped to the higher numbered suffix. In that case it is strongly advised to use the nonsuffixed API entry to guarantee backward compatibiliy with the following cuDNN release.
2.11. Grouped Convolutions
cuDNN supports grouped convolutions by setting groupCount > 1 for the convolution descriptor convDesc
, using cudnnSetConvolutionGroupCount()
.
By default the convolution descriptor convDesc
is set to groupCount of 1.
Basic Idea
Conceptually, in grouped convolutions the input channels and the filter channels are split into groupCount number of independent groups, with each group having a reduced number of channels. Convolution operation is then performed separately on these input and filter groups.
For example, consider the following: if the number of input channels is 4, and the number of filter channels of 12. For a normal, ungrouped convolution, the number of computation operations performed are 12*4.
If the groupCount is set to 2, then there are now two input channel groups of two input channels each, and two filter channel groups of six filter channels each.
As a result, each grouped convolution will now perform 2*6 computation operations, and two such grouped convolutions are performed. Hence the computation savings are 2x: (12*4)/(2*(2*6))
 When using
groupCount
for grouped convolutions, you must still define all tensor descriptors so that they describe the size of the entire convolution, instead of specifying the sizes per group.  Grouped convolutions are supported for all formats that are currently supported by the functions
cuDNNConvolutionForward()
,cudnnConvolutionBackwardData()
andcudnnConvolutionBackwardFilter()
.  The tensor stridings that are set for
groupCount
of 1 are also valid for any group count.  By default the convolution descriptor
convDesc
is set togroupCount
of 1.
See Convolution Formulas for the math behind the cuDNN Grouped Convolution.
Example
Below is an example showing the dimensions and strides for grouped convolutions for NCHW format, for 2D convolution.
Note that the symbols "*" and "/" are used to indicate multiplication and division.
 Dimensions:
[batch_size, input_channel, x_height, x_width]
 Strides:
[input_channels*x_height*x_width, x_height*x_width, x_width, 1]
 Dimensions:
[output_channels, input_channels/groupCount, w_height, w_width]
 Format:
NCHW
 Group Count:
groupCount
 Dimensions:
[batch_size, output_channels, y_height, y_width]
Strides: [output_channels*y_height*y_width, y_height*y_width, y_width, 1]
2.12. API Logging
cuDNN API logging is a tool that records all input parameters passed into every cuDNN API function call. This functionality is disabled by default, and can be enabled through methods described in this section.
The log output contains variable names, data types, parameter values, device pointers, process ID, thread ID, cuDNN handle, cuda stream ID, and metadata such as time of the function call in microseconds.
When logging is enabled, the log output will be handled by the builtin default callback function. The user may also write their own callback function, and use the cudnnSetCallback
to pass in the function pointer of their own callback function. The following is a sample output of the API log.
Function cudnnSetActivationDescriptor() called:
mode: type=cudnnActivationMode_t; val=CUDNN_ACTIVATION_RELU (1);
reluNanOpt: type=cudnnNanPropagation_t; val=CUDNN_NOT_PROPAGATE_NAN (0);
coef: type=double; val=1000.000000;
Time: 20171121T14:14:21.366171 (0d+0h+1m+5s since start)
Process: 21264, Thread: 21264, cudnn_handle: NULL, cudnn_stream: NULL.
There are two methods to enable API logging.
Method 1: Using Environment Variables
To enable API logging using environment variables, follow these steps:
 Set the environment variable
CUDNN_LOGINFO_DBG
to “1”, and  Set the environment varialbe
CUDNN_LOGDEST_DBG
to one of the following:stdout
,stderr
, or a userdesired file path, for example,/home/userName1/log.txt
.
 Include the conversion specifiers in the file name. For example:
 To include date and time in the file name, use the date and time conversion specificers:
log_%Y_%m_%d_%H_%M_%S.txt
. The conversion specifiers will be automatically replaced with the date and time when the program is initiated, resulting inlog_2017_11_21_09_41_00.txt
.  To include the process id in the file name, use the
%i
conversion specifier:log_%Y_%m_%d_%H_%M_%S_%i.txt
for the result:log_2017_11_21_09_41_00_21264.txt
when the process id is21264
. When you have several processes running, using the process id conversion specifier will prevent these processes writing to the same file at the same time.
Note:The supported conversion specifiers are similar to the
strftime
function.
If the file already exists, the log will overwrite the existing file.
Note:These environmental variables are only checked once at the initialization. Any subsequent changes in these environmental variables will not be effective in the current run. Also note that these environment settings can be overridden by the Method 2 below.
 To include date and time in the file name, use the date and time conversion specificers:
See also Table 1 for the impact on performance of API logging using environment variables.
Environment variables  CUDNN_LOGINFO_DBG=0  CUDNN_LOGINFO_DBG=1 

CUDNN_LOGDEST_DBG not set 
 No logging output  No performance loss 
 No logging output  No performance loss 
CUDNN_LOGDEST_DBG= 
 No logging output  No performance loss 
 No logging output  No performance loss 
CUDNN_LOGDEST_DBG= 
 No logging output  No performance loss 
 Logging to  Some performance loss 
CUDNN_LOGDEST_DBG=

 No logging output  No performance loss 
 Logging to  Some performance loss 
Method 2
Method 2: To use API function calls to enable API logging, refer to the API description of cudnnSetCallback()
and cudnnGetCallback()
.
2.13. Features of RNN Functions
 cudnnRNNForwardInference
 cudnnRNNForwardTraining
 cudnnRNNBackwardData
 cudnnRNNBackwardWeights
 cudnnRNNForwardInferenceEx
 cudnnRNNForwardTrainingEx
 cudnnRNNBackwardDataEx
 cudnnRNNBackwardWeightsEx
See the table below for a list of features supported by each RNN function:
For each of these terms, the shortform versions shown in the paranthesis are used in the tables below for brevity: CUDNN_RNN_ALGO_STANDARD
(_ALGO_STANDARD), CUDNN_RNN_ALGO_PERSIST_STATIC
(_ALGO_PERSIST_STATIC), CUDNN_RNN_ALGO_PERSIST_DYNAMIC
(_ALGO_PERSIST_DYNAMIC), and CUDNN_TENSOR_OP_MATH_ALLOW_CONVERSION
(_ALLOW_CONVERSION).
Functions  Input output layout supported  Supports variable sequence length in batch  Commonly supported 
cudnnRNNForwardInference 
Only Sequence major, packed (nonpadded)  Only with Require input sequences descending sorted according to length 
Mode (cell type) supported:
Algo supported* (see the table below for an elaboration on these algorithms):
Math mode supported:
(will automatically fall back if run on preVolta, or if algo doesn’t support HMMA acceleration)
Direction mode supported:
RNN input mode:



cudnnRNNBackwardData 



cudnnRNNForwardInferenceEx 
Sequence major unpacked, Batch major unpacked**, Sequence major packed** 
Only with For unpacked layout**, no input sorting required. For packed layout, require input sequences descending sorted according to length 



cudnnRNNBackwardDataEx 

cudnnRNNBackwardWeightsEx 
* Do not mix different algos for different steps of training. It’s also not recommended to mix nonextended and extended API for different steps of training.
** To use unpacked layout, user need to set CUDNN_RNN_PADDED_IO_ENABLED through cudnnSetRNNPaddingMode
.
The following table provides the features supported by the algorithms referred in the above table: CUDNN_RNN_ALGO_STANDARD
, CUDNN_RNN_ALGO_PERSIST_STATIC
, and CUDNN_RNN_ALGO_PERSIST_DYNAMIC
.
Features  _ALGO_STANDARD 
_ALGO_PERSIST_STATIC 
_ALGO_PERSIST_DYNAMIC 
Half input Single accumulation Half output 
Supported Half intermediate storage Single accumulation 

Single input Single accumulation Single output 
Supported If running on Volta, with Otherwise: Single intermediate storage Single accumulation 

Double input Double accumulation Double output 
Supported Double intermediate storage Double accumulation 
Not Supported  Supported Double intermediate storage Double accumulation 
LSTM recurrent projection  Supported  Not Supported  Not Supported 
LSTM cell clipping  Supported  
Variable sequence length in batch  Supported  Not Supported  Not Supported 
HMMA acceleration on Volta/Xavier  Supported For half input/output, acceleration requires setting
Acceleration requires For single input/output, acceleration requires setting
Acceleration requires 
Not Supported, will execute normally ignoring CUDNN_TENSOR_OP_MATH^{!} or


Other limitations  Max problem size is limited by GPU specifications.  Requires real time compilation through NVRTC 
!CUDNN_TENSOR_OP_MATH
or CUDNN_TENSOR_OP_MATH_ALLOW_CONVERSION
can be set through cudnnSetRNNMatrixMathType
.
2.14. Mixed Precision Numerical Accuracy
When the computation precision and the output precision are not the same, it is possible that the numerical accuracy will vary from one algorithm to the other.
For example, when the computation is performed in FP32 and the output is in FP16, the CUDNN_CONVOLUTION_BWD_FILTER_ALGO_0 ("ALGO_0") has lower accuracy compared to the CUDNN_CONVOLUTION_BWD_FILTER_ALGO_1 ("ALGO_1"). This is because ALGO_0 does not use extra workspace, and is forced to accumulate the intermediate results in FP16, i.e., half precision float, and this reduces the accuracy. The ALGO_1, on the other hand, uses additonal workspace to accumulate the intermediate values in FP32, i.e., full precision float.
This chapter describes all the types and enums of the cuDNN library API.
3.1. cudnnActivationDescriptor_t
cudnnActivationDescriptor_t
is a pointer to an opaque structure holding the description of a activation operation. cudnnCreateActivationDescriptor()
is used to create one instance, and cudnnSetActivationDescriptor()
must be used to initialize this instance.
3.2. cudnnActivationMode_t
cudnnActivationMode_t
is an enumerated type used to select the neuron activation function used in cudnnActivationForward()
, cudnnActivationBackward()
and cudnnConvolutionBiasActivationForward()
.
Values

CUDNN_ACTIVATION_SIGMOID

Selects the sigmoid function.

CUDNN_ACTIVATION_RELU

Selects the rectified linear function.

CUDNN_ACTIVATION_TANH

Selects the hyperbolic tangent function.

CUDNN_ACTIVATION_CLIPPED_RELU

Selects the clipped rectified linear function.

CUDNN_ACTIVATION_ELU

Selects the exponential linear function.

CUDNN_ACTIVATION_IDENTITY (new for 7.1)

Selects the identity function, intended for bypassing the activation step in
cudnnConvolutionBiasActivationForward().
(ThecudnnConvolutionBiasActivationForward()
function must use CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_PRECOMP_GEMM.) Does not work withcudnnActivationForward()
orcudnnActivationBackward()
.
3.3. cudnnBatchNormMode_t
cudnnBatchNormMode_t
is an enumerated type used to specify the mode of operation in cudnnBatchNormalizationForwardInference()
, cudnnBatchNormalizationForwardTraining()
, cudnnBatchNormalizationBackward()
and cudnnDeriveBNTensorDescriptor()
routines.
Values

CUDNN_BATCHNORM_PER_ACTIVATION

Normalization is performed peractivation. This mode is intended to be used after nonconvolutional network layers. In this mode the tensor dimensions of
bnBias
andbnScale
, the parameters used in the cudnnBatchNormalization* functions, are 1xCxHxW. 
CUDNN_BATCHNORM_SPATIAL

Normalization is performed over N+spatial dimensions. This mode is intended for use after convolutional layers (where spatial invariance is desired). In this mode the
bnBias
,bnScale
tensor dimensions are 1xCx1x1. 
CUDNN_BATCHNORM_SPATIAL_PERSISTENT

This mode is similar to CUDNN_BATCHNORM_SPATIAL but it can be faster for some tasks.
An optimized path may be selected for CUDNN_DATA_FLOAT and CUDNN_DATA_HALF types, compute capability 6.0 or higher for the following two batch normalization API calls:
cudnnBatchNormalizationForwardTraining()
, andcudnnBatchNormalizationBackward()
. In the case of cudnnBatchNormalizationBackward(), thesavedMean
andsavedInvVariance
arguments should not be NULL.The rest of this section applies for
NCHW
mode only:This mode may use a scaled atomic integer reduction that is deterministic but imposes more restrictions on the input data range. When a numerical overflow occurs the algorithm may produce NaNs or Infs (infinity) in output buffers.
When Infs/NaNs are present in the input data, the output in this mode is the same as from a pure floatingpoint implementation.
For finite but very large input values, the algorithm may encounter overflows more frequently due to a lower dynamic range and emit Infs/NaNs while CUDNN_BATCHNORM_SPATIAL will produce finite results. The user can invoke
cudnnQueryRuntimeError()
to check if a numerical overflow occurred in this mode.
3.4. cudnnBatchNormOps_t
cudnnBatchNormOps_t
is an enumerated type used to specify the mode of operation in cudnnGetBatchNormalizationForwardTrainingExWorkspaceSize()
, cudnnBatchNormalizationForwardTrainingEx()
, cudnnGetBatchNormalizationBackwardExWorkspaceSize()
, cudnnBatchNormalizationBackwardEx()
, and cudnnGetBatchNormalizationTrainingExReserveSpaceSize()
functions.
Values

CUDNN_BATCHNORM_OPS_BN

Only batch normalization is performed, peractivation.

CUDNN_BATCHNORM_OPS_BN_ACTIVATION

First the batch normalization is performed, and then the activation is performed.

CUDNN_BATCHNORM_OPS_BN_ADD_ACTIVATION

Performs the batch normalization, then elementwise addition, followed by the activation operation.
3.5. cudnnCTCLossAlgo_t
cudnnCTCLossAlgo_t
is an enumerated type that exposes the different algorithms available to execute the CTC loss operation.
Values

CUDNN_CTC_LOSS_ALGO_DETERMINISTIC

Results are guaranteed to be reproducible

CUDNN_CTC_LOSS_ALGO_NON_DETERMINISTIC

Results are not guaranteed to be reproducible
3.6. cudnnCTCLossDescriptor_t
cudnnCTCLossDescriptor_t
is a pointer to an opaque structure holding the description of a CTC loss operation. cudnnCreateCTCLossDescriptor()
is used to create one instance, cudnnSetCTCLossDescriptor()
is be used to initialize this instance, cudnnDestroyCTCLossDescriptor()
is be used to destroy this instance.
3.7. cudnnConvolutionBwdDataAlgoPerf_t
cudnnConvolutionBwdDataAlgoPerf_t
is a structure containing performance results returned by cudnnFindConvolutionBackwardDataAlgorithm()
or heuristic results returned by cudnnGetConvolutionBackwardDataAlgorithm_v7()
.
Data Members

cudnnConvolutionBwdDataAlgo_t algo

The algorithm run to obtain the associated performance metrics.

cudnnStatus_t status

If any error occurs during the workspace allocation or timing of
cudnnConvolutionBackwardData()
, this status will represent that error. Otherwise, this status will be the return status ofcudnnConvolutionBackwardData()
.CUDNN_STATUS_ALLOC_FAILED
if any error occured during workspace allocation or if provided workspace is insufficient.CUDNN_STATUS_INTERNAL_ERROR
if any error occured during timing calculations or workspace deallocation. Otherwise, this will be the return status of
cudnnConvolutionBackwardData()
.

float time

The execution time of
cudnnConvolutionBackwardData()
(in milliseconds). 
size_t memory

The workspace size (in bytes).

cudnnDeterminism_t determinism

The determinism of the algorithm.

cudnnMathType_t mathType

The math type provided to the algorithm.

int reserved[3]

Reserved space for future properties.
3.8. cudnnConvolutionBwdDataAlgo_t
cudnnConvolutionBwdDataAlgo_t
is an enumerated type that exposes the different algorithms available to execute the backward data convolution operation.
Values

CUDNN_CONVOLUTION_BWD_DATA_ALGO_0

This algorithm expresses the convolution as a sum of matrix product without actually explicitly form the matrix that holds the input tensor data. The sum is done using atomic adds operation, thus the results are nondeterministic.

CUDNN_CONVOLUTION_BWD_DATA_ALGO_1

This algorithm expresses the convolution as a matrix product without actually explicitly form the matrix that holds the input tensor data. The results are deterministic.

CUDNN_CONVOLUTION_BWD_DATA_ALGO_FFT

This algorithm uses a FastFourier Transform approach to compute the convolution. A significant memory workspace is needed to store intermediate results. The results are deterministic.

CUDNN_CONVOLUTION_BWD_DATA_ALGO_FFT_TILING

This algorithm uses the FastFourier Transform approach but splits the inputs into tiles. A significant memory workspace is needed to store intermediate results but less than CUDNN_CONVOLUTION_BWD_DATA_ALGO_FFT for large size images. The results are deterministic.

CUDNN_CONVOLUTION_BWD_DATA_ALGO_WINOGRAD

This algorithm uses the Winograd Transform approach to compute the convolution. A reasonably sized workspace is needed to store intermediate results. The results are deterministic.

CUDNN_CONVOLUTION_BWD_DATA_ALGO_WINOGRAD_NONFUSED

This algorithm uses the Winograd Transform approach to compute the convolution. Significant workspace may be needed to store intermediate results. The results are deterministic.
3.9. cudnnConvolutionBwdDataPreference_t
cudnnConvolutionBwdDataPreference_t
is an enumerated type used by cudnnGetConvolutionBackwardDataAlgorithm()
to help the choice of the algorithm used for the backward data convolution.
Values

CUDNN_CONVOLUTION_BWD_DATA_NO_WORKSPACE

In this configuration, the routine
cudnnGetConvolutionBackwardDataAlgorithm()
is guaranteed to return an algorithm that does not require any extra workspace to be provided by the user. 
CUDNN_CONVOLUTION_BWD_DATA_PREFER_FASTEST

In this configuration, the routine
cudnnGetConvolutionBackwardDataAlgorithm()
will return the fastest algorithm regardless how much workspace is needed to execute it. 
CUDNN_CONVOLUTION_BWD_DATA_SPECIFY_WORKSPACE_LIMIT

In this configuration, the routine
cudnnGetConvolutionBackwardDataAlgorithm()
will return the fastest algorithm that fits within the memory limit that the user provided.
3.10. cudnnConvolutionBwdFilterAlgoPerf_t
cudnnConvolutionBwdFilterAlgoPerf_t
is a structure containing performance results returned by cudnnFindConvolutionBackwardFilterAlgorithm()
or heuristic results returned by cudnnGetConvolutionBackwardFilterAlgorithm_v7()
.
Data Members

cudnnConvolutionBwdFilterAlgo_t algo

The algorithm run to obtain the associated performance metrics.

cudnnStatus_t status

If any error occurs during the workspace allocation or timing of
cudnnConvolutionBackwardFilter()
, this status will represent that error. Otherwise, this status will be the return status ofcudnnConvolutionBackwardFilter()
.CUDNN_STATUS_ALLOC_FAILED
if any error occured during workspace allocation or if provided workspace is insufficient.CUDNN_STATUS_INTERNAL_ERROR
if any error occured during timing calculations or workspace deallocation. Otherwise, this will be the return status of
cudnnConvolutionBackwardFilter()
.

float time

The execution time of
cudnnConvolutionBackwardFilter()
(in milliseconds). 
size_t memory

The workspace size (in bytes).

cudnnDeterminism_t determinism

The determinism of the algorithm.

cudnnMathType_t mathType

The math type provided to the algorithm.

int reserved[3]

Reserved space for future properties.
3.11. cudnnConvolutionBwdFilterAlgo_t
cudnnConvolutionBwdFilterAlgo_t
is an enumerated type that exposes the different algorithms available to execute the backward filter convolution operation.
Values

CUDNN_CONVOLUTION_BWD_FILTER_ALGO_0

This algorithm expresses the convolution as a sum of matrix product without actually explicitly form the matrix that holds the input tensor data. The sum is done using atomic adds operation, thus the results are nondeterministic.

CUDNN_CONVOLUTION_BWD_FILTER_ALGO_1

This algorithm expresses the convolution as a matrix product without actually explicitly form the matrix that holds the input tensor data. The results are deterministic.

CUDNN_CONVOLUTION_BWD_FILTER_ALGO_FFT

This algorithm uses the FastFourier Transform approach to compute the convolution. Significant workspace is needed to store intermediate results. The results are deterministic.

CUDNN_CONVOLUTION_BWD_FILTER_ALGO_3

This algorithm is similar to
CUDNN_CONVOLUTION_BWD_FILTER_ALGO_0
but uses some small workspace to precomputes some indices. The results are also nondeterministic. 
CUDNN_CONVOLUTION_BWD_FILTER_WINOGRAD_NONFUSED

This algorithm uses the Winograd Transform approach to compute the convolution. Significant workspace may be needed to store intermediate results. The results are deterministic.

CUDNN_CONVOLUTION_BWD_FILTER_ALGO_FFT_TILING

This algorithm uses the FastFourier Transform approach to compute the convolution but splits the input tensor into tiles. Significant workspace may be needed to store intermediate results. The results are deterministic.
3.12. cudnnConvolutionBwdFilterPreference_t
cudnnConvolutionBwdFilterPreference_t
is an enumerated type used by cudnnGetConvolutionBackwardFilterAlgorithm()
to help the choice of the algorithm used for the backward filter convolution.
Values

CUDNN_CONVOLUTION_BWD_FILTER_NO_WORKSPACE

In this configuration, the routine
cudnnGetConvolutionBackwardFilterAlgorithm()
is guaranteed to return an algorithm that does not require any extra workspace to be provided by the user. 
CUDNN_CONVOLUTION_BWD_FILTER_PREFER_FASTEST

In this configuration, the routine
cudnnGetConvolutionBackwardFilterAlgorithm()
will return the fastest algorithm regardless how much workspace is needed to execute it. 
CUDNN_CONVOLUTION_BWD_FILTER_SPECIFY_WORKSPACE_LIMIT

In this configuration, the routine
cudnnGetConvolutionBackwardFilterAlgorithm()
will return the fastest algorithm that fits within the memory limit that the user provided.
3.13. cudnnConvolutionDescriptor_t
cudnnConvolutionDescriptor_t
is a pointer to an opaque structure holding the description of a convolution operation. cudnnCreateConvolutionDescriptor()
is used to create one instance, and cudnnSetConvolutionNdDescriptor()
or cudnnSetConvolution2dDescriptor()
must be used to initialize this instance.
3.14. cudnnConvolutionFwdAlgoPerf_t
cudnnConvolutionFwdAlgoPerf_t
is a structure containing performance results returned by cudnnFindConvolutionForwardAlgorithm()
or heuristic results returned by cudnnGetConvolutionForwardAlgorithm_v7()
.
Data Members

cudnnConvolutionFwdAlgo_t algo

The algorithm run to obtain the associated performance metrics.

cudnnStatus_t status

If any error occurs during the workspace allocation or timing of
cudnnConvolutionForward()
, this status will represent that error. Otherwise, this status will be the return status ofcudnnConvolutionForward()
.CUDNN_STATUS_ALLOC_FAILED
if any error occured during workspace allocation or if provided workspace is insufficient.CUDNN_STATUS_INTERNAL_ERROR
if any error occured during timing calculations or workspace deallocation. Otherwise, this will be the return status of
cudnnConvolutionForward()
.

float time

The execution time of
cudnnConvolutionForward()
(in milliseconds). 
size_t memory

The workspace size (in bytes).

cudnnDeterminism_t determinism

The determinism of the algorithm.

cudnnMathType_t mathType

The math type provided to the algorithm.

int reserved[3]

Reserved space for future properties.
3.15. cudnnConvolutionFwdAlgo_t
cudnnConvolutionFwdAlgo_t
is an enumerated type that exposes the different algorithms available to execute the forward convolution operation.
Values

CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_GEMM

This algorithm expresses the convolution as a matrix product without actually explicitly form the matrix that holds the input tensor data.

CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_PRECOMP_GEMM

This algorithm expresses the convolution as a matrix product without actually explicitly form the matrix that holds the input tensor data, but still needs some memory workspace to precompute some indices in order to facilitate the implicit construction of the matrix that holds the input tensor data.

CUDNN_CONVOLUTION_FWD_ALGO_GEMM

This algorithm expresses the convolution as an explicit matrix product. A significant memory workspace is needed to store the matrix that holds the input tensor data.

CUDNN_CONVOLUTION_FWD_ALGO_DIRECT

This algorithm expresses the convolution as a direct convolution (e.g without implicitly or explicitly doing a matrix multiplication).

CUDNN_CONVOLUTION_FWD_ALGO_FFT

This algorithm uses the FastFourier Transform approach to compute the convolution. A significant memory workspace is needed to store intermediate results.

CUDNN_CONVOLUTION_FWD_ALGO_FFT_TILING

This algorithm uses the FastFourier Transform approach but splits the inputs into tiles. A significant memory workspace is needed to store intermediate results but less than
CUDNN_CONVOLUTION_FWD_ALGO_FFT
for large size images. 
CUDNN_CONVOLUTION_FWD_ALGO_WINOGRAD

This algorithm uses the Winograd Transform approach to compute the convolution. A reasonably sized workspace is needed to store intermediate results.

CUDNN_CONVOLUTION_FWD_ALGO_WINOGRAD_NONFUSED

This algorithm uses the Winograd Transform approach to compute the convolution. Significant workspace may be needed to store intermediate results.
3.16. cudnnConvolutionFwdPreference_t
cudnnConvolutionFwdPreference_t
is an enumerated type used by cudnnGetConvolutionForwardAlgorithm()
to help the choice of the algorithm used for the forward convolution.
Values

CUDNN_CONVOLUTION_FWD_NO_WORKSPACE

In this configuration, the routine
cudnnGetConvolutionForwardAlgorithm()
is guaranteed to return an algorithm that does not require any extra workspace to be provided by the user. 
CUDNN_CONVOLUTION_FWD_PREFER_FASTEST

In this configuration, the routine
cudnnGetConvolutionForwardAlgorithm()
will return the fastest algorithm regardless how much workspace is needed to execute it. 
CUDNN_CONVOLUTION_FWD_SPECIFY_WORKSPACE_LIMIT

In this configuration, the routine
cudnnGetConvolutionForwardAlgorithm()
will return the fastest algorithm that fits within the memory limit that the user provided.
3.17. cudnnConvolutionMode_t
cudnnConvolutionMode_t
is an enumerated type used by cudnnSetConvolutionDescriptor()
to configure a convolution descriptor. The filter used for the convolution can be applied in two different ways, corresponding mathematically to a convolution or to a crosscorrelation. (A crosscorrelation is equivalent to a convolution with its filter rotated by 180 degrees.)
Values

CUDNN_CONVOLUTION

In this mode, a convolution operation will be done when applying the filter to the images.

CUDNN_CROSS_CORRELATION

In this mode, a crosscorrelation operation will be done when applying the filter to the images.
3.18. cudnnDataType_t
cudnnDataType_t
is an enumerated type indicating the data type to which a tensor descriptor or filter descriptor refers.
Values

CUDNN_DATA_FLOAT

The data is 32bit singleprecision floating point (
float
). 
CUDNN_DATA_DOUBLE

The data is 64bit doubleprecision floating point (
double
). 
CUDNN_DATA_HALF

The data is 16bit floating point.

CUDNN_DATA_INT8

The data is 8bit signed integer.

CUDNN_DATA_UINT8 (new for 7.1)

The data is 8bit unsigned integer.

CUDNN_DATA_INT32

The data is 32bit signed integer.

CUDNN_DATA_INT8x4

The data is 32bit elements each composed of 4 8bit signed integer. This data type is only supported with tensor format CUDNN_TENSOR_NCHW_VECT_C.

CUDNN_DATA_INT8x32

The data is 32element vectors, each element being 8bit signed integer. This data type is only supported with the tensor format CUDNN_TENSOR_NCHW_VECT_C. Moreover, this data type can only be used with “algo 1,” i.e., CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_PRECOMP_GEMM. See cudnnConvolutionFwdAlgo_t.

CUDNN_DATA_UINT8x4 (new for 7.1)

The data is 32bit elements each composed of 4 8bit unsigned integer. This data type is only supported with tensor format CUDNN_TENSOR_NCHW_VECT_C.
3.19. cudnnDeterminism_t
cudnnDeterminism_t
is an enumerated type used to indicate if the computed results are deterministic (reproducible). See section 2.5 (Reproducibility) for more details on determinism.
Values

CUDNN_NON_DETERMINISTIC

Results are not guaranteed to be reproducible

CUDNN_DETERMINISTIC

Results are guaranteed to be reproducible
3.20. cudnnDirectionMode_t
cudnnDirectionMode_t
is an enumerated type used to specify the recurrence pattern in the cudnnRNNForwardInference()
, cudnnRNNForwardTraining()
, cudnnRNNBackwardData()
and cudnnRNNBackwardWeights()
routines.
Values

CUDNN_UNIDIRECTIONAL
 The network iterates recurrently from the first input to the last.

CUDNN_BIDIRECTIONAL
 Each layer of the the network iterates recurrently from the first input to the last and separately from the last input to the first. The outputs of the two are concatenated at each iteration giving the output of the layer.
3.21. cudnnDivNormMode_t
cudnnDivNormMode_t
is an enumerated type used to specify the mode of operation in cudnnDivisiveNormalizationForward()
and cudnnDivisiveNormalizationBackward()
.
Values

CUDNN_DIVNORM_PRECOMPUTED_MEANS

The means tensor data pointer is expected to contain means or other kernel convolution values precomputed by the user. The means pointer can also be NULL, in that case it's considered to be filled with zeroes. This is equivalent to spatial LRN. Note that in the backward pass the means are treated as independent inputs and the gradient over means is computed independently. In this mode to yield a net gradient over the entire LCN computational graph the destDiffMeans result should be backpropagated through the user's means layer (which can be impelemented using average pooling) and added to the destDiffData tensor produced by cudnnDivisiveNormalizationBackward.
3.22. cudnnDropoutDescriptor_t
cudnnDropoutDescriptor_t
is a pointer to an opaque structure holding the description of a dropout operation. cudnnCreateDropoutDescriptor()
is used to create one instance, cudnnSetDropoutDescriptor()
is used to initialize this instance, cudnnDestroyDropoutDescriptor()
is used to destroy this instance, cudnnGetDropoutDescriptor()
is used to query fields of a previously initialized instance, cudnnRestoreDropoutDescriptor()
is used to restore an instance to a previously saved off state.
3.23. cudnnErrQueryMode_t
cudnnErrQueryMode_t
is an enumerated type passed to cudnnQueryRuntimeError()
to select the remote kernel error query mode.
Values

CUDNN_ERRQUERY_RAWCODE
 Read the error storage location regardless of the kernel completion status.

CUDNN_ERRQUERY_NONBLOCKING
 Report if all tasks in the user stream of the cuDNN handle were completed. If that is the case, report the remote kernel error code.

CUDNN_ERRQUERY_BLOCKING
 Wait for all tasks to complete in the user stream before reporting the remote kernel error code.
3.24. cudnnFilterDescriptor_t
cudnnFilterDescriptor_t
is a pointer to an opaque structure holding the description of a filter dataset. cudnnCreateFilterDescriptor()
is used to create one instance, and cudnnSetFilter4dDescriptor()
or cudnnSetFilterNdDescriptor()
must be used to initialize this instance.
3.25. cudnnHandle_t
cudnnHandle_t
is a pointer to an opaque structure holding the cuDNN library context. The cuDNN library context must be created using cudnnCreate()
and the returned handle must be passed to all subsequent library function calls. The context should be destroyed at the end using cudnnDestroy()
. The context is associated with only one GPU device, the current device at the time of the call to cudnnCreate()
. However multiple contexts can be created on the same GPU device.
3.26. cudnnIndicesType_t
cudnnIndicesType_t
is an enumerated type used to indicate the data type for the indices to be computed by the cudnnReduceTensor()
routine. This enumerated type is used as a field for the cudnnReduceTensorDescriptor_t
descriptor.
Values

CUDNN_32BIT_INDICES

Compute unsigned int indices

CUDNN_64BIT_INDICES

Compute unsigned long long indices

CUDNN_16BIT_INDICES

Compute unsigned short indices

CUDNN_8BIT_INDICES

Compute unsigned char indices
3.27. cudnnLRNMode_t
cudnnLRNMode_t
is an enumerated type used to specify the mode of operation in cudnnLRNCrossChannelForward()
and cudnnLRNCrossChannelBackward()
.
Values

CUDNN_LRN_CROSS_CHANNEL_DIM1

LRN computation is performed across tensor's dimension dimA[1].
3.28. cudnnMathType_t
cudnnMathType_t
is an enumerated type used to indicate if the use of Tensor Core Operations is permitted a given library routine.
Values

CUDNN_DEFAULT_MATH

Tensor Core Operations are not used.

CUDNN_TENSOR_OP_MATH

The use of Tensor Core Operations is permitted.

CUDNN_TENSOR_OP_MATH_ALLOW_CONVERSION

Enables the use of FP32 tensors for both input and output.
3.29. cudnnNanPropagation_t
cudnnNanPropagation_t
is an enumerated type used to indicate if a given routine should propagate Nan
numbers. This enumerated type is used as a field for the cudnnActivationDescriptor_t
descriptor and cudnnPoolingDescriptor_t
descriptor.
Values

CUDNN_NOT_PROPAGATE_NAN

Nan
numbers are not propagated 
CUDNN_PROPAGATE_NAN

Nan
numbers are propagated
3.30. cudnnOpTensorDescriptor_t
cudnnOpTensorDescriptor_t
is a pointer to an opaque structure holding the description of a Tensor Ccore Operation, used as a parameter to cudnnOpTensor()
. cudnnCreateOpTensorDescriptor()
is used to create one instance, and cudnnSetOpTensorDescriptor()
must be used to initialize this instance.
3.31. cudnnOpTensorOp_t
cudnnOpTensorOp_t
is an enumerated type used to indicate the Tensor Core Operation to be used by the cudnnOpTensor()
routine. This enumerated type is used as a field for the cudnnOpTensorDescriptor_t
descriptor.
Values

CUDNN_OP_TENSOR_ADD

The operation to be performed is addition

CUDNN_OP_TENSOR_MUL

The operation to be performed is multiplication

CUDNN_OP_TENSOR_MIN

The operation to be performed is a minimum comparison

CUDNN_OP_TENSOR_MAX

The operation to be performed is a maximum comparison

CUDNN_OP_TENSOR_SQRT

The operation to be performed is square root, performed on only the A tensor

CUDNN_OP_TENSOR_NOT

The operation to be performed is negation, performed on only the A tensor
3.32. cudnnPersistentRNNPlan_t
cudnnPersistentRNNPlan_t
is a pointer to an opaque structure holding a plan to execute a dynamic persistent RNN. cudnnCreatePersistentRNNPlan()
is used to create and initialize one instance.
3.33. cudnnPoolingDescriptor_t
cudnnPoolingDescriptor_t
is a pointer to an opaque structure holding the description of a pooling operation. cudnnCreatePoolingDescriptor()
is used to create one instance, and cudnnSetPoolingNdDescriptor()
or cudnnSetPooling2dDescriptor()
must be used to initialize this instance.
3.34. cudnnPoolingMode_t
cudnnPoolingMode_t
is an enumerated type passed to cudnnSetPoolingDescriptor()
to select the pooling method to be used by cudnnPoolingForward()
and cudnnPoolingBackward()
.
Values

CUDNN_POOLING_MAX

The maximum value inside the pooling window is used.

CUDNN_POOLING_AVERAGE_COUNT_INCLUDE_PADDING

Values inside the pooling window are averaged. The number of elements used to calculate the average includes spatial locations falling in the padding region.

CUDNN_POOLING_AVERAGE_COUNT_EXCLUDE_PADDING

Values inside the pooling window are averaged. The number of elements used to calculate the average excludes spatial locations falling in the padding region.

CUDNN_POOLING_MAX_DETERMINISTIC

The maximum value inside the pooling window is used. The algorithm used is deterministic.
3.35. cudnnRNNAlgo_t
cudnnRNNAlgo_t
is an enumerated type used to specify the algorithm used in the cudnnRNNForwardInference()
, cudnnRNNForwardTraining()
, cudnnRNNBackwardData()
and cudnnRNNBackwardWeights()
routines.
Values

CUDNN_RNN_ALGO_STANDARD
 Each RNN layer is executed as a sequence of operations. This algorithm is expected to have robust performance across a wide range of network parameters.

CUDNN_RNN_ALGO_PERSIST_STATIC

The recurrent parts of the network are executed using a persistent kernel approach. This method is expected to be fast when the first dimension of the input tensor is small (ie. a small minibatch).
CUDNN_RNN_ALGO_PERSIST_STATIC
is only supported on devices with compute capability >= 6.0. 
CUDNN_RNN_ALGO_PERSIST_DYNAMIC

The recurrent parts of the network are executed using a persistent kernel approach. This method is expected to be fast when the first dimension of the input tensor is small (ie. a small minibatch). When using
CUDNN_RNN_ALGO_PERSIST_DYNAMIC
persistent kernels are prepared at runtime and are able to optimized using the specific parameters of the network and active GPU. As such, when usingCUDNN_RNN_ALGO_PERSIST_DYNAMIC
a onetime plan preparation stage must be executed. These plans can then be reused in repeated calls with the same model parameters.The limits on the maximum number of hidden units supported when using
CUDNN_RNN_ALGO_PERSIST_DYNAMIC
are significantly higher than the limits when usingCUDNN_RNN_ALGO_PERSIST_STATIC
, however throughput is likely to significantly reduce when exceeding the maximums supported byCUDNN_RNN_ALGO_PERSIST_STATIC
. In this regime this method will still outperformCUDNN_RNN_ALGO_STANDARD
for some cases.CUDNN_RNN_ALGO_PERSIST_DYNAMIC
is only supported on devices with compute capability >= 6.0 on Linux machines.
3.36. cudnnRNNClipMode_t
cudnnRNNClipMode_t
is an enumerated type used to select the LSTM cell clipping mode. It is used with cudnnRNNSetClip()
, cudnnRNNGetClip()
functions, and internally within LSTM cells.
Values

CUDNN_RNN_CLIP_NONE

Disables LSTM cell clipping.

CUDNN_RNN_CLIP_MINMAX

Enables LSTM cell clipping.
3.37. cudnnRNNDescriptor_t
cudnnRNNDescriptor_t
is a pointer to an opaque structure holding the description of an RNN operation. cudnnCreateRNNDescriptor()
is used to create one instance, and cudnnSetRNNDescriptor()
must be used to initialize this instance.
3.38. cudnnRNNDataDescriptor_t
cudnnRNNDataDescriptor_t
is a pointer to an opaque structure holding the description of a RNN data set. The function cudnnCreateRNNDataDescriptor()
is used to create one instance, and cudnnSetRNNDataDescriptor()
must be used to initialize this instance.
3.39. cudnnRNNInputMode_t
cudnnRNNInputMode_t
is an enumerated type used to specify the behavior of the first layer in the cudnnRNNForwardInference()
, cudnnRNNForwardTraining()
, cudnnRNNBackwardData()
and cudnnRNNBackwardWeights()
routines.
Values

CUDNN_LINEAR_INPUT
 A biased matrix multiplication is performed at the input of the first recurrent layer.

CUDNN_SKIP_INPUT

No operation is performed at the input of the first recurrent layer. If
CUDNN_SKIP_INPUT
is used the leading dimension of the input tensor must be equal to the hidden state size of the network.
3.40. cudnnRNNMode_t
cudnnRNNMode_t
is an enumerated type used to specify the type of network used in the cudnnRNNForwardInference()
, cudnnRNNForwardTraining()
, cudnnRNNBackwardData()
and cudnnRNNBackwardWeights()
routines.
Values

CUDNN_RNN_RELU

A singlegate recurrent neural network with a ReLU activation function.
In the forward pass the output
h_{t}
for a given iteration can be computed from the recurrent inputh_{t1}
and the previous layer inputx_{t}
given matricesW, R
and biasesb_{W}, b_{R}
from the following equation:h_{t} = ReLU(W_{i}x_{t} + R_{i}h_{t1} + b_{Wi} + b_{Ri})
Where
ReLU(x) = max(x, 0)
. 
CUDNN_RNN_TANH

A singlegate recurrent neural network with a tanh activation function.
In the forward pass the output
h_{t}
for a given iteration can be computed from the recurrent inputh_{t1}
and the previous layer inputx_{t}
given matricesW, R
and biasesb_{W}, b_{R}
from the following equation:h_{t} = tanh(W_{i}x_{t} + R_{i}h_{t1} + b_{Wi} + b_{Ri})
Where
tanh
is the hyperbolic tangent function. 
CUDNN_LSTM

A fourgate Long ShortTerm Memory network with no peephole connections.
In the forward pass the output
h_{t}
and cell outputc_{t}
for a given iteration can be computed from the recurrent inputh_{t1}
, the cell inputc_{t1}
and the previous layer inputx_{t}
given matricesW, R
and biasesb_{W}, b_{R}
from the following equations:i_{t} = σ(W_{i}x_{t} + R_{i}h_{t1} + b_{Wi} + b_{Ri}) f_{t} = σ(W_{f}x_{t} + R_{f}h_{t1} + b_{Wf} + b_{Rf}) o_{t} = σ(W_{o}x_{t} + R_{o}h_{t1} + b_{Wo} + b_{Ro}) c'_{t} = tanh(W_{c}x_{t} + R_{c}h_{t1} + b_{Wc} + b_{Rc}) c_{t} = f_{t}◦c_{t1} + i_{t}◦c'_{t} h_{t} = o_{t}◦tanh(c_{t})
Where
σ
is the sigmoid operator:σ(x) = 1 / (1 + e^{x})
,◦
represents a pointwise multiplication andtanh
is the hyperbolic tangent function.i_{t}, f_{t}, o_{t}, c'_{t}
represent the input, forget, output and new gates respectively. 
CUDNN_GRU

A threegate network consisting of Gated Recurrent Units.
In the forward pass the output
h_{t}
for a given iteration can be computed from the recurrent inputh_{t1}
and the previous layer inputx_{t}
given matricesW, R
and biasesb_{W}, b_{R}
from the following equations:i_{t} = σ(W_{i}x_{t} + R_{i}h_{t1} + b_{Wi} + b_{Ru}) r_{t} = σ(W_{r}x_{t} + R_{r}h_{t1} + b_{Wr} + b_{Rr}) h'_{t} = tanh(W_{h}x_{t} + r_{t}◦(R_{h}h_{t1} + b_{Rh}) + b_{Wh}) h_{t} = (1  i_{t})◦h'_{t} + i_{t}◦h_{t1}
Where
σ
is the sigmoid operator:σ(x) = 1 / (1 + e^{x})
,◦
represents a pointwise multiplication andtanh
is the hyperbolic tangent function.i_{t}, r_{t}, h'_{t}
represent the input, reset, new gates respectively.
3.41. cudnnRNNPaddingMode_t
cudnnRNNPaddingMode_t
is an enumerated type used to enable or disable the padded input/output.
Values

CUDNN_RNN_PADDED_IO_DISABLED
 Disables the padded input/output.

CUDNN_RNN_PADDED_IO_ENABLED
 Enables the padded input/output.
3.42. cudnnReduceTensorDescriptor_t
cudnnReduceTensorDescriptor_t
is a pointer to an opaque structure holding the description of a tensor reduction operation, used as a parameter to cudnnReduceTensor()
. cudnnCreateReduceTensorDescriptor()
is used to create one instance, and cudnnSetReduceTensorDescriptor()
must be used to initialize this instance.
cudnnReduceTensorIndices_t
cudnnReduceTensorIndices_t
is an enumerated type used to indicate whether indices are to be computed by the cudnnReduceTensor()
routine. This enumerated type is used as a field for the cudnnReduceTensorDescriptor_t
descriptor.
Values

CUDNN_REDUCE_TENSOR_NO_INDICES

Do not compute indices

CUDNN_REDUCE_TENSOR_FLATTENED_INDICES

Compute indices. The resulting indices are relative, and flattened.
3.44. cudnnReduceTensorOp_t
cudnnReduceTensorOp_t
is an enumerated type used to indicate the Tensor Core Operation to be used by the cudnnReduceTensor()
routine. This enumerated type is used as a field for the cudnnReduceTensorDescriptor_t
descriptor.
Values

CUDNN_REDUCE_TENSOR_ADD

The operation to be performed is addition

CUDNN_REDUCE_TENSOR_MUL

The operation to be performed is multiplication

CUDNN_REDUCE_TENSOR_MIN

The operation to be performed is a minimum comparison

CUDNN_REDUCE_TENSOR_MAX

The operation to be performed is a maximum comparison

CUDNN_REDUCE_TENSOR_AMAX

The operation to be performed is a maximum comparison of absolute values

CUDNN_REDUCE_TENSOR_AVG

The operation to be performed is averaging

CUDNN_REDUCE_TENSOR_NORM1

The operation to be performed is addition of absolute values

CUDNN_REDUCE_TENSOR_NORM2

The operation to be performed is a square root of sum of squares

CUDNN_REDUCE_TENSOR_MUL_NO_ZEROS

The operation to be performed is multiplication, not including elements of value zero
3.45. cudnnSamplerType_t
cudnnSamplerType_t
is an enumerated type passed to cudnnSetSpatialTransformerNdDescriptor()
to select the sampler type to be used by cudnnSpatialTfSamplerForward()
and cudnnSpatialTfSamplerBackward()
.
Values

CUDNN_SAMPLER_BILINEAR
 Selects the bilinear sampler.
3.46. cudnnSoftmaxAlgorithm_t
cudnnSoftmaxAlgorithm_t
is used to select an implementation of the softmax function used in cudnnSoftmaxForward()
and cudnnSoftmaxBackward()
.
Values

CUDNN_SOFTMAX_FAST

This implementation applies the straightforward softmax operation.

CUDNN_SOFTMAX_ACCURATE

This implementation scales each point of the softmax input domain by its maximum value to avoid potential floating point overflows in the softmax evaluation.

CUDNN_SOFTMAX_LOG

This entry performs the Log softmax operation, avoiding overflows by scaling each point in the input domain as in
CUDNN_SOFTMAX_ACCURATE
3.47. cudnnSoftmaxMode_t
cudnnSoftmaxMode_t
is used to select over which data the cudnnSoftmaxForward()
and cudnnSoftmaxBackward()
are computing their results.
Values

CUDNN_SOFTMAX_MODE_INSTANCE

The softmax operation is computed per image (N) across the dimensions C,H,W.

CUDNN_SOFTMAX_MODE_CHANNEL

The softmax operation is computed per spatial location (H,W) per image (N) across the dimension C.
3.48. cudnnSpatialTransformerDescriptor_t
cudnnSpatialTransformerDescriptor_t
is a pointer to an opaque structure holding the description of a spatial transformation operation. cudnnCreateSpatialTransformerDescriptor()
is used to create one instance, cudnnSetSpatialTransformerNdDescriptor()
is used to initialize this instance, cudnnDestroySpatialTransformerDescriptor()
is used to destroy this instance.
3.49. cudnnStatus_t
cudnnStatus_t
is an enumerated type used for function status returns. All cuDNN library functions return their status, which can be one of the following values:
Values

CUDNN_STATUS_SUCCESS

The operation completed successfully.

CUDNN_STATUS_NOT_INITIALIZED

The cuDNN library was not initialized properly. This error is usually returned when a call to
cudnnCreate()
fails or whencudnnCreate()
has not been called prior to calling another cuDNN routine. In the former case, it is usually due to an error in the CUDA Runtime API called bycudnnCreate()
or by an error in the hardware setup. 
CUDNN_STATUS_ALLOC_FAILED

Resource allocation failed inside the cuDNN library. This is usually caused by an internal
cudaMalloc()
failure.To correct: prior to the function call, deallocate previously allocated memory as much as possible.

CUDNN_STATUS_BAD_PARAM

An incorrect value or parameter was passed to the function.
To correct: ensure that all the parameters being passed have valid values.

CUDNN_STATUS_ARCH_MISMATCH

The function requires a feature absent from the current GPU device. Note that cuDNN only supports devices with compute capabilities greater than or equal to 3.0.
To correct: compile and run the application on a device with appropriate compute capability.

CUDNN_STATUS_MAPPING_ERROR

An access to GPU memory space failed, which is usually caused by a failure to bind a texture.
To correct: prior to the function call, unbind any previously bound textures.
Otherwise, this may indicate an internal error/bug in the library.

CUDNN_STATUS_EXECUTION_FAILED

The GPU program failed to execute. This is usually caused by a failure to launch some cuDNN kernel on the GPU, which can occur for multiple reasons.
To correct: check that the hardware, an appropriate version of the driver, and the cuDNN library are correctly installed.
Otherwise, this may indicate a internal error/bug in the library.

CUDNN_STATUS_INTERNAL_ERROR

An internal cuDNN operation failed.

CUDNN_STATUS_NOT_SUPPORTED

The functionality requested is not presently supported by cuDNN.

CUDNN_STATUS_LICENSE_ERROR

The functionality requested requires some license and an error was detected when trying to check the current licensing. This error can happen if the license is not present or is expired or if the environment variable NVIDIA_LICENSE_FILE is not set properly.

CUDNN_STATUS_RUNTIME_PREREQUISITE_MISSING

Runtime library required by RNN calls (libcuda.so or nvcuda.dll) cannot be found in predefined search paths.

CUDNN_STATUS_RUNTIME_IN_PROGRESS

Some tasks in the user stream are not completed.

CUDNN_STATUS_RUNTIME_FP_OVERFLOW

Numerical overflow occurred during the GPU kernel execution.
3.50. cudnnTensorDescriptor_t
cudnnCreateTensorDescriptor_t
is a pointer to an opaque structure holding the description of a generic nD dataset. cudnnCreateTensorDescriptor()
is used to create one instance, and one of the routrines cudnnSetTensorNdDescriptor()
, cudnnSetTensor4dDescriptor()
or cudnnSetTensor4dDescriptorEx()
must be used to initialize this instance.
3.51. cudnnTensorFormat_t
cudnnTensorFormat_t
is an enumerated type used by cudnnSetTensor4dDescriptor()
to create a tensor with a predefined layout.
Values

CUDNN_TENSOR_NCHW

This tensor format specifies that the data is laid out in the following order: batch size, feature maps, rows, columns. The strides are implicitly defined in such a way that the data are contiguous in memory with no padding between images, feature maps, rows, and columns; the columns are the inner dimension and the images are the outermost dimension.

CUDNN_TENSOR_NHWC

This tensor format specifies that the data is laid out in the following order: batch size, rows, columns, feature maps. The strides are implicitly defined in such a way that the data are contiguous in memory with no padding between images, rows, columns, and feature maps; the feature maps are the inner dimension and the images are the outermost dimension.

CUDNN_TENSOR_NCHW_VECT_C

This tensor format specifies that the data is laid out in the following order: batch size, feature maps, rows, columns. However, each element of the tensor is a vector of multiple feature maps. The length of the vector is carried by the data type of the tensor. The strides are implicitly defined in such a way that the data are contiguous in memory with no padding between images, feature maps, rows, and columns; the columns are the inner dimension and the images are the outermost dimension. This format is only supported with tensor data types CUDNN_DATA_INT8x4, CUDNN_DATA_INT8x32, and CUDNN_DATA_UINT8x4.
This chapter describes the API of all the routines of the cuDNN library.
4.1. cudnnActivationBackward
cudnnStatus_t cudnnActivationBackward(
cudnnHandle_t handle,
cudnnActivationDescriptor_t activationDesc,
const void *alpha,
const cudnnTensorDescriptor_t yDesc,
const void *y,
const cudnnTensorDescriptor_t dyDesc,
const void *dy,
const cudnnTensorDescriptor_t xDesc,
const void *x,
const void *beta,
const cudnnTensorDescriptor_t dxDesc,
void *dx)
This routine computes the gradient of a neuron activation function.
Inplace operation is allowed for this routine; i.e. dy
and dx
pointers may be equal. However, this requires the corresponding tensor descriptors to be identical (particularly, the strides of the input and output must match for inplace operation to be allowed).
All tensor formats are supported for 4 and 5 dimensions, however best performance is obtained when the strides of yDesc
and xDesc
are equal and HWpacked
. For more than 5 dimensions the tensors must have their spatial dimensions packed.
Parameters
 handle

Input. Handle to a previously created cuDNN context. See cudnnHandle_t.
 activationDesc

Input. Activation descriptor. See cudnnActivationDescriptor_t.
 alpha, beta

Input. Pointers to scaling factors (in host memory) used to blend the computation result with prior value in the output layer as follows: dstValue = alpha[0]*result + beta[0]*priorDstValue. Refer to this section for additional details.
 yDesc

Input. Handle to the previously initialized input tensor descriptor. See cudnnTensorDescriptor_t.
 y

Input. Data pointer to GPU memory associated with the tensor descriptor
yDesc
.  dyDesc

Input. Handle to the previously initialized input differential tensor descriptor.
 dy

Input. Data pointer to GPU memory associated with the tensor descriptor
dyDesc
.  xDesc

Input. Handle to the previously initialized output tensor descriptor.
 x

Input. Data pointer to GPU memory associated with the output tensor descriptor
xDesc
.  dxDesc

Input. Handle to the previously initialized output differential tensor descriptor.
 dx

Output. Data pointer to GPU memory associated with the output tensor descriptor
dxDesc
.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The function launched successfully.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The strides
nStride, cStride, hStride, wStride
of the input differential tensor and output differential tensors differ and inplace operation is used.
 The strides

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration. See the following for some examples of nonsupported configurations:
 The dimensions
n,c,h,w
of the input tensor and output tensors differ.  The
datatype
of the input tensor and output tensors differs.  The strides
nStride, cStride, hStride, wStride
of the input tensor and the input differential tensor differ.  The strides
nStride, cStride, hStride, wStride
of the output tensor and the output differential tensor differ.
 The dimensions

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.
4.2. cudnnActivationForward
cudnnStatus_t cudnnActivationForward(
cudnnHandle_t handle,
cudnnActivationDescriptor_t activationDesc,
const void *alpha,
const cudnnTensorDescriptor_t xDesc,
const void *x,
const void *beta,
const cudnnTensorDescriptor_t yDesc,
void *y)
This routine applies a specified neuron activation function elementwise over each input value.
Inplace operation is allowed for this routine; i.e., xData
and yData
pointers may be equal. However, this requires xDesc
and yDesc
descriptors to be identical (particularly, the strides of the input and output must match for inplace operation to be allowed).
All tensor formats are supported for 4 and 5 dimensions, however best performance is obtained when the strides of xDesc
and yDesc
are equal and HWpacked
. For more than 5 dimensions the tensors must have their spatial dimensions packed.
Parameters
 handle

Input. Handle to a previously created cuDNN context. See cudnnHandle_t.
 activationDesc

Input. Activation descriptor. See cudnnActivationDescriptor_t.
 alpha, beta

Input. Pointers to scaling factors (in host memory) used to blend the computation result with prior value in the output layer as follows: dstValue = alpha[0]*result + beta[0]*priorDstValue. Please refer to this section for additional details.
 xDesc

Input. Handle to the previously initialized input tensor descriptor. See cudnnTensorDescriptor_t.
 x

Input. Data pointer to GPU memory associated with the tensor descriptor
xDesc
.  yDesc

Input. Handle to the previously initialized output tensor descriptor.
 y

Output. Data pointer to GPU memory associated with the output tensor descriptor
yDesc
.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The function launched successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The parameter
mode
has an invalid enumerant value.  The dimensions
n,c,h,w
of the input tensor and output tensors differ.  The
datatype
of the input tensor and output tensors differs.  The strides
nStride,cStride,hStride,wStride
of the input tensor and output tensors differ and inplace operation is used (i.e.,x
andy
pointers are equal).
 The parameter

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.
4.3. cudnnAddTensor
cudnnStatus_t cudnnAddTensor(
cudnnHandle_t handle,
const void *alpha,
const cudnnTensorDescriptor_t aDesc,
const void *A,
const void *beta,
const cudnnTensorDescriptor_t cDesc,
void *C)
This function adds the scaled values of a bias tensor to another tensor. Each dimension of the bias tensor A
must match the corresponding dimension of the destination tensor C
or must be equal to 1. In the latter case, the same value from the bias tensor for those dimensions will be used to blend into the C
tensor.
Up to dimension 5, all tensor formats are supported. Beyond those dimensions, this routine is not supported
Parameters
 handle

Input. Handle to a previously created cuDNN context. See cudnnHandle_t.
 alpha, beta

Input. Pointers to scaling factors (in host memory) used to blend the source value with prior value in the destination tensor as follows: dstValue = alpha[0]*srcValue + beta[0]*priorDstValue. Refer to this section for additional details.
 aDesc

Input. Handle to a previously initialized tensor descriptor. See cudnnTensorDescriptor_t.
 A

Input. Pointer to data of the tensor described by the
aDesc
descriptor.  cDesc

Input. Handle to a previously initialized tensor descriptor.
 C

Input/Output. Pointer to data of the tensor described by the
cDesc
descriptor.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The function executed successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

The dimensions of the bias tensor refer to an amount of data that is incompatible the output tensor dimensions or the
dataType
of the two tensor descriptors are different. 
CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.
4.4. cudnnBatchNormalizationBackward
cudnnStatus_t cudnnBatchNormalizationBackward(
cudnnHandle_t handle,
cudnnBatchNormMode_t mode,
const void *alphaDataDiff,
const void *betaDataDiff,
const void *alphaParamDiff,
const void *betaParamDiff,
const cudnnTensorDescriptor_t xDesc,
const void *x,
const cudnnTensorDescriptor_t dyDesc,
const void *dy,
const cudnnTensorDescriptor_t dxDesc,
void *dx,
const cudnnTensorDescriptor_t bnScaleBiasDiffDesc,
const void *bnScale,
void *resultBnScaleDiff,
void *resultBnBiasDiff,
double epsilon,
const void *savedMean,
const void *savedInvVariance)
This function performs the backward batch normalization layer computation. This layer is based on the paper Batch Normalization: Accelerating Deep Network Training by Reducing Internal Covariate Shift, S. Ioffe, C. Szegedy, 2015.
See cudnnDeriveBNTensorDescriptor
for the secondary tensor descriptor generation for the parameters using in this function.
Only 4D and 5D tensors are supported.
The epsilon
value has to be the same during training, backpropagation and inference.
Higher performance can be obtained when HWpacked tensors are used for all of x, dy, dx
.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor. See cudnnHandle_t.
 mode

Input. Mode of operation (spatial or peractivation). See cudnnBatchNormMode_t.
 *alphaDataDiff, *betaDataDiff

Inputs. Pointers to scaling factors (in host memory) used to blend the gradient output
dx
with a prior value in the destination tensor as follows:dstValue = alphaDataDiff[0]*resultValue + betaDataDiff[0]*priorDstValue.
Refer to this section for additional details.  *alphaParamDiff, *betaParamDiff

Inputs. Pointers to scaling factors (in host memory) used to blend the gradient outputs
resultBnScaleDiff
andresultBnBiasDiff
with prior values in the destination tensor as follows:dstValue = alphaParamDiff[0]*resultValue + betaParamDiff[0]*priorDstValue.
Refer to this section for additional details.  xDesc, dxDesc, dyDesc

Inputs. Handles to the previously initialized tensor descriptors.
 *x

Input. Data pointer to GPU memory associated with the tensor descriptor
xDesc
, for the layer’sx
data.  *dy

Inputs. Data pointer to GPU memory associated with the tensor descriptor
dyDesc
, for the backpropagated differentialdy
input.  *dx

Inputs. Data pointer to GPU memory associated with the tensor descriptor
dxDesc
, for the resulting differential output with respect tox
.  bnScaleBiasDiffDesc

Input. Shared tensor descriptor for the following five tensors:
bnScale, resultBnScaleDiff, resultBnBiasDiff, savedMean, savedInvVariance
. The dimensions for this tensor descriptor are dependent on normalization mode. See cudnnDeriveBNTensorDescriptor.Note:The data type of this tensor descriptor must be 'float' for FP16 and FP32 input tensors, and 'double' for FP64 input tensors.
 *bnScale

Input. Pointer in the device memory for the batch normalization
scale
parameter (in original paper the quantityscale
is referred to as gamma).Note:The
bnBias
parameter is not needed for this layer's computation.  resultBnScaleDiff, resultBnBiasDiff
 Outputs. Pointers in device memory for the resulting scale and bias differentials computed by this routine. Note that these scale and bias gradients are weight gradients specific to this batch normalization operation, and by definition are not backpropagated.
 epsilon

Input. Epsilon value used in batch normalization formula. The value should be more than the value that is defined for CUDNN_BN_MIN_EPSILON in the header file cudnn.h. Same
epsilon
value should be used in forward and backward functions.  *savedMean, *savedInvVariance

Inputs. Optional cache parameters containing saved intermediate results that were computed during the forward pass. For this to work correctly, the layer's
x
andbnScale
data has to remain unchanged until this backward function is called.Note:Both these parameters can be NULL but only at the same time. It is recommended to use this cache since the memory overhead is relatively small.
Returns

CUDNN_STATUS_SUCCESS

The computation was performed successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 Any of the pointers
alpha, beta, x, dy, dx, bnScale, resultBnScaleDiff, resultBnBiasDiff
is NULL.  Number of
xDesc
oryDesc
ordxDesc
tensor descriptor dimensions is not within the range of [4,5] (only 4D and 5D tensors are supported.) bnScaleBiasDiffDesc
dimensions are not 1xCx1x1 for 4D and 1xCx1x1x1 for 5D for spatial, and are not 1xCxHxW for 4D and 1xCxDxHxW for 5D for peractivation mode. Exactly one of
savedMean
,savedInvVariance
pointers is NULL. epsilon
value is less than CUDNN_BN_MIN_EPSILON. Dimensions or data types mismatch for any pair of
xDesc, dyDesc, dxDesc.
 Any of the pointers
4.5. cudnnBatchNormalizationBackwardEx
cudnnStatus_t cudnnBatchNormalizationBackwardEx (
cudnnHandle_t handle,
cudnnBatchNormMode_t mode,
cudnnBatchNormOps_t bnOps,
const void *alphaDataDiff,
const void *betaDataDiff,
const void *alphaParamDiff,
const void *betaParamDiff,
const cudnnTensorDescriptor_t xDesc,
const void *xData,
const cudnnTensorDescriptor_t yDesc,
const void *yData,
const cudnnTensorDescriptor_t dyDesc,
const void *dyData,
const cudnnTensorDescriptor_t dzDesc,
void *dzData,
const cudnnTensorDescriptor_t dxDesc,
void *dxData,
const cudnnTensorDescriptor_t dBnScaleBiasDesc,
const void *bnScaleData,
const void *bnBiasData,
void *dBnScaleData,
void *dBnBiasData,
double epsilon,
const void *savedMean,
const void *savedInvVariance,
const cudnnActivationDescriptor_t activationDesc,
void *workspace,
size_t workSpaceSizeInBytes
void *reserveSpace
size_t reserveSpaceSizeInBytes);
This function is an extension of the cudnnBatchNormalizationBackward()
for performing the backward batch normalization layer computation with a fast NHWC semipersistent kernel. This API will trigger the new semipersistent NHWC kernel when the below conditions are true:

All tensors, namely,
x, y, dz, dy, dx
must be NHWCfully packed, and must be of the type CUDNN_DATA_HALF. 
The tensor C dimension should be a multiple of 4.

The input parameter
mode
must be set to CUDNN_BATCHNORM_SPATIAL_PERSISTENT. 
workspace
is not NULL. 
workSpaceSizeInBytes
is equal or larger than the amount required by cudnnGetBatchNormalizationBackwardExWorkspaceSize(). 
reserveSpaceSizeInBytes
is equal or larger than the amount required by cudnnGetBatchNormalizationTrainingExReserveSpaceSize(). 
The content in
reserveSpace
stored by cudnnBatchNormalizationForwardTrainingEx() must be preserved.
If workspace
is NULL and workSpaceSizeInBytes
of zero is passed in, this API will function exactly like the nonextended function cudnnBatchNormalizationBackward
.
This workspace is not required to be clean. Moreover, the workspace does not have to remain unchanged between the forward and backward pass, as it is not used for passing any information.
This extended function can accept a *workspace
pointer to the GPU workspace, and workSpaceSizeInBytes,
the size of the workspace, from the user.
The bnOps
input can be used to set this function to perform either only the batch normalization, or batch normalization followed by activation, or batch normalization followed by elementwise addition and then activation.
Only 4D and 5D tensors are supported. The epsilon
value has to be the same during the training, the backpropagation and the inference.
When the tensor layout is NCHW, higher performance can be obtained when HWpacked tensors are used for x, dy, dx
.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor. See cudnnHandle_t.
 mode

Input. Mode of operation (spatial or peractivation). See cudnnBatchNormMode_t.
 bnOps
 Input. Mode of operation for the fast NHWC kernel. See cudnnBatchNormOps_t.. This input can be used to set this function to perform either only the batch normalization, or batch normalization followed by activation, or batch normalization followed by elementwise addition and then activation.
 *alphaDataDiff, *betaDataDiff

Inputs. Pointers to scaling factors (in host memory) used to blend the gradient output
dx
with a prior value in the destination tensor as follows:dstValue = alpha[0]*resultValue + beta[0]*priorDstValue.
Refer to this section for additional details.  *alphaParamDiff, *betaParamDiff

Inputs. Pointers to scaling factors (in host memory) used to blend the gradient outputs
dBnScaleData
anddBnBiasData
with prior values in the destination tensor as follows:dstValue = alpha[0]*resultValue + beta[0]*priorDstValue.
Refer to this section for additional details.  xDesc, *x,yDesc, *yData, dyDesc, *dyData, dzDesc, *dzData, dxDesc, *dx/dt

Inputs. Tensor descriptors and pointers in the device memory for the layer's
x
data, back propagated differentialdy
(inputs), the optionaly
input data, the optionaldz
output, and thedx
output, which is the resulting differential with respect tox.
See cudnnTensorDescriptor_t.  dBnScaleBiasDesc

Input. Shared tensor descriptor for the following six tensors:
bnScaleData, bnBiasData, dBnScaleData, dBnBiasData, savedMean, and savedInvVariance.
See cudnnDeriveBNTensorDescriptor.The dimensions for this tensor descriptor are dependent on normalization mode.
Note:Note: The data type of this tensor descriptor must be 'float' for FP16 and FP32 input tensors, and 'double' for FP64 input tensors.
 *bnScaleData

Input. Pointer in the device memory for the batch normalization scale parameter (in the original paper the quantity scale is referred to as gamma).
 *bnBiasData
 Input. Pointers in the device memory for the batch normalization bias parameter (in the original paper bias is referred to as beta). This parameter is used only when activation should be performed.
 *dBnScaleData, dBnBiasData

Inputs. Pointers in the device memory for the gradients of
bnScaleData
andbnBiasData
, respectively.  epsilon

Input. Epsilon value used in batch normalization formula. Minimum allowed value is CUDNN_BN_MIN_EPSILON defined in cudnn.h. Same epsilon value should be used in forward and backward functions.
 *savedMean, *savedInvVariance

Inputs. Optional cache parameters containing saved intermediate results computed during the forward pass. For this to work correctly, the layer's
x
andbnScaleData
,bnBiasData
data has to remain unchanged until this backward function is called. Note that both these parameters can be NULL but only at the same time. It is recommended to use this cache since the memory overhead is relatively small.  activationDesc
 Input. Tensor descriptor for the activation operation.
 workspace

Input. Pointer to the GPU workspace. If
workspace
is NULL andworkSpaceSizeInBytes
of zero is passed in, then this API will function exactly like the nonextended function cudnnBatchNormalizationBackward().  workSpaceSizeInBytes
 Input. The size of the workspace. Must be large enough to trigger the fast NHWC semipersistent kernel by this function.
 *reserveSpace

Input. Pointer to the GPU workspace for the
reserveSpace
.  reserveSpaceSizeInBytes

Input. The size of the
reserveSpace
. Must be equal or larger than the amount required bycudnnGetBatchNormalizationTrainingExReserveSpaceSize()
.
Returns

CUDNN_STATUS_SUCCESS

The computation was performed successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 Any of the pointers
alphaDataDiff, betaDataDiff, alphaParamDiff, betaParamDiff, x, dy, dx, bnScale, resultBnScaleDiff, resultBnBiasDiff
is NULL.  Number of
xDesc
oryDesc
ordxDesc
tensor descriptor dimensions is not within the range of [4,5] (only 4D and 5D tensors are supported.) dBnScaleBiasDesc
dimensions not 1xCx1x1 for 4D and 1xCx1x1x1 for 5D for spatial, and are not 1xCxHxW for 4D and 1xCxDxHxW for 5D for peractivation mode. . Exactly one of
savedMean
,savedInvVariance
pointers is NULL. epsilon
value is less than CUDNN_BN_MIN_EPSILON. Dimensions or data types mismatch for any pair of
xDesc
,dyDesc
,dxDesc
.
 Any of the pointers
4.6. cudnnBatchNormalizationForwardInference
cudnnStatus_t cudnnBatchNormalizationForwardInference(
cudnnHandle_t handle,
cudnnBatchNormMode_t mode,
const void *alpha,
const void *beta,
const cudnnTensorDescriptor_t xDesc,
const void *x,
const cudnnTensorDescriptor_t yDesc,
void *y,
const cudnnTensorDescriptor_t bnScaleBiasMeanVarDesc,
const void *bnScale,
const void *bnBias,
const void *estimatedMean,
const void *estimatedVariance,
double epsilon)
This function performs the forward batch normalization layer computation for the inference phase. This layer is based on the paper Batch Normalization: Accelerating Deep Network Training by Reducing Internal Covariate Shift, S. Ioffe, C. Szegedy, 2015.
See cudnnDeriveBNTensorDescriptor
for the secondary tensor descriptor generation for the parameters using in this function.
Only 4D and 5D tensors are supported.
The input transformation performed by this function is defined as:
y = beta*y + alpha *[bnBias + (bnScale * (xestimatedMean)/sqrt(epsilon + estimatedVariance)]
The epsilon
value has to be the same during training, backpropagation and inference.
For training phase use cudnnBatchNormalizationForwardTraining
.
Higher performance can be obtained when HWpacked tensors are used for all of x
and dx
.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor. See cudnnHandle_t.
 mode

Input. Mode of operation (spatial or peractivation). See cudnnBatchNormMode_t.
 alpha, beta

Inputs. Pointers to scaling factors (in host memory) used to blend the layer output value with prior value in the destination tensor as follows:
dstValue = alpha[0]*resultValue + beta[0]*priorDstValue.
Refer to this section for additional details.  xDesc, yDesc

Input. Handles to the previously initialized tensor descriptors.
 *x

Input. Data pointer to GPU memory associated with the tensor descriptor
xDesc
, for the layer’sx
input data.  *y

Input. Data pointer to GPU memory associated with the tensor descriptor
yDesc
, for they
output of the batch normalization layer.  bnScaleBiasMeanVarDesc, bnScale, bnBias

Inputs. Tensor descriptor and pointers in device memory for the batch normalization scale and bias parameters (in the original paper bias is referred to as beta and scale as gamma).
 estimatedMean, estimatedVariance

Inputs. Mean and variance tensors (these have the same descriptor as the bias and scale). The
resultRunningMean
andresultRunningVariance
, accumulated during the training phase from thecudnnBatchNormalizationForwardTraining()
call, should be passed as inputs here.  epsilon

Input. Epsilon value used in the batch normalization formula. The value should be more than the value defined for CUDNN_BN_MIN_EPSILON in the cudnn.h header file.
Returns

CUDNN_STATUS_SUCCESS

The computation was performed successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the pointers
alpha, beta, x, y, bnScale, bnBias, estimatedMean, estimatedInvVariance
is NULL.  Number of
xDesc
oryDesc
tensor descriptor dimensions is not within the range of [4,5] (only 4D and 5D tensors are supported.) bnScaleBiasMeanVarDesc
dimensions are not 1xCx1x1 for 4D and 1xCx1x1x1 for 5D for spatial, and are not 1xCxHxW for 4D and 1xCxDxHxW for 5D for peractivation mode.epsilon
value is less than CUDNN_BN_MIN_EPSILON. Dimensions or data types mismatch for
xDesc
,yDesc.
 One of the pointers
4.7. cudnnBatchNormalizationForwardTraining
cudnnStatus_t cudnnBatchNormalizationForwardTraining(
cudnnHandle_t handle,
cudnnBatchNormMode_t mode,
const void *alpha,
const void *beta,
const cudnnTensorDescriptor_t xDesc,
const void *x,
const cudnnTensorDescriptor_t yDesc,
void *y,
const cudnnTensorDescriptor_t bnScaleBiasMeanVarDesc,
const void *bnScale,
const void *bnBias,
double exponentialAverageFactor,
void *resultRunningMean,
void *resultRunningVariance,
double epsilon,
void *resultSaveMean,
void *resultSaveInvVariance)
This function performs the forward batch normalization layer computation for the training phase. This layer is based on the paper Batch Normalization: Accelerating Deep Network Training by Reducing Internal Covariate Shift, S. Ioffe, C. Szegedy, 2015.
See cudnnDeriveBNTensorDescriptor
for the secondary tensor descriptor generation for the parameters using in this function.
Only 4D and 5D tensors are supported.
The epsilon value has to be the same during training, backpropagation and inference.
For inference phase use cudnnBatchNormalizationForwardInference.
Higher performance can be obtained when HWpacked tensors are used for both x and y.
Parameters
 handle

Handle to a previously created cuDNN library descriptor. See cudnnHandle_t.
 mode

Mode of operation (spatial or peractivation). See cudnnBatchNormMode_t.
 alpha, beta

Inputs. Pointers to scaling factors (in host memory) used to blend the layer output value with prior value in the destination tensor as follows:
dstValue = alpha[0]*resultValue + beta[0]*priorDstValue.
Refer to this section for additional details.  xDesc, yDesc

Tensor descriptors and pointers in device memory for the layer's
x
andy
data. See cudnnTensorDescriptor_t.  *x

Input. Data pointer to GPU memory associated with the tensor descriptor
xDesc
, for the layer’sx
input data.  *y

Input. Data pointer to GPU memory associated with the tensor descriptor
yDesc
, for they
output of the batch normalization layer.  bnScaleBiasMeanVarDesc

Shared tensor descriptor desc for the secondary tensor that was derived by cudnnDeriveBNTensorDescriptor. The dimensions for this tensor descriptor are dependent on the normalization mode.
 bnScale, bnBias

Inputs. Pointers in device memory for the batch normalization scale and bias parameters (in the original paper bias is referred to as beta and scale as gamma). Note that
bnBias
parameter can replace the previous layer's bias parameter for improved efficiency.  exponentialAverageFactor

Input. Factor used in the moving average computation as follows:
runningMean = runningMean*(1factor) + newMean*factor
Use afactor=1/(1+n)
atN
th call to the function to get Cumulative Moving Average (CMA) behavior such that:CMA[n] = (x[1]+...+x[n])/n
. This is proved below: WritingCMA[n+1] = (n*CMA[n]+x[n+1])/(n+1)
= ((n+1)*CMA[n]CMA[n])/(n+1) + x[n+1]/(n+1)
= CMA[n]*(11/(n+1))+x[n+1]*1/(n+1)
= CMA[n]*(1factor) + x(n+1)*factor.
 resultRunningMean, resultRunningVariance

Inputs/Outputs. Running mean and variance tensors (these have the same descriptor as the bias and scale). Both of these pointers can be NULL but only at the same time. The value stored in
resultRunningVariance
(or passed as an input in inference mode) is the sample variance, and is the moving average of variance[x] where variance is computed either over batch or spatial+batch dimensions depending on the mode. If these pointers are not NULL, the tensors should be initialized to some reasonable values or to 0.  epsilon

Input. Epsilon value used in the batch normalization formula. The value should be more than the value defined for CUDNN_BN_MIN_EPSILON in the cudnn.h header file. Same
epsilon
value should be used in forward and backward functions.  resultSaveMean, resultSaveInvVariance

Outputs. Optional cache to save intermediate results computed during the forward pass. These buffers can be used to speed up the backward pass when supplied to the
cudnnBatchNormalizationBackward()
function. The intermediate results stored inresultSaveMean
andresultSaveInvVariance
buffers should not be used directly by the user. Depending on the batch normalization mode, the results stored inresultSaveInvVariance
may vary. For the cache to work correctly, the input layer data must remain unchanged until the backward function is called. Note that both parameters can be NULL but only at the same time. In such a case intermediate statistics will not be saved, andcudnnBatchNormalizationBackward()
will have to recompute them. It is recommended to use this cache as the memory overhead is relatively small because these tensors have a much lower product of dimensions than the data tensors.
Returns

CUDNN_STATUS_SUCCESS

The computation was performed successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the pointers
alpha, beta, x, y, bnScale, bnBias
is NULL.  Number of
xDesc
oryDesc
tensor descriptor dimensions is not within the range of [4,5] (only 4D and 5D tensors are supported.) bnScaleBiasMeanVarDesc
dimensions are not 1xCx1x1 for 4D and 1xCx1x1x1 for 5D for spatial, and are not 1xCxHxW for 4D and 1xCxDxHxW for 5D for peractivation mode. Exactly one of
resultSaveMean
,resultSaveInvVariance
pointers is NULL.  Exactly one of
resultRunningMean
,resultRunningInvVariance
pointers is NULL. epsilon
value is less than CUDNN_BN_MIN_EPSILON. Dimensions or data types mismatch for
xDesc
,yDesc
 One of the pointers
4.8. cudnnBatchNormalizationForwardTrainingEx
cudnnStatus_t cudnnBatchNormalizationForwardTrainingEx(
cudnnHandle_t handle,
cudnnBatchNormMode_t mode,
cudnnBatchNormOps_t bnOps,
const void *alpha,
const void *beta,
const cudnnTensorDescriptor_t xDesc,
const void *xData,
const cudnnTensorDescriptor_t zDesc,
const void *zData,
const cudnnTensorDescriptor_t yDesc,
void *yData,
const cudnnTensorDescriptor_t bnScaleBiasMeanVarDesc,
const void *bnScaleData,
const void *bnBiasData,
double exponentialAverageFactor,
void *resultRunningMeanData,
void *resultRunningVarianceData,
double epsilon,
void *saveMean,
void *saveInvVariance,
const cudnnActivationDescriptor_t activationDesc,
void *workspace,
size_t workSpaceSizeInBytes
void *reserveSpace
size_t reserveSpaceSizeInBytes);
This function is an extension of the cudnnBatchNormalizationForwardTraining()
for performing the forward batch normalization layer computation.
This API will trigger the new semipersistent NHWC kernel when the below conditions are true:

All tensors, namely,
x, y, dz, dy, dx
must be NHWCfully packed, and must be of the type CUDNN_DATA_HALF. 
The tensor C dimension should be a multiple of 4.

The input parameter
mode
must be set to CUDNN_BATCHNORM_SPATIAL_PERSISTENT. 
workspace
is not NULL. 
workSpaceSizeInBytes
is equal or larger than the amount required bycudnnGetBatchNormalizationForwardTrainingExWorkspaceSize
(). 
reserveSpaceSizeInBytes
is equal or larger than the amount required bycudnnGetBatchNormalizationTrainingExReserveSpaceSize()
. 
The content in
reserveSpace
stored by cudnnBatchNormalizationForwardTrainingEx() must be preserved.
If workspace
is NULL and workSpaceSizeInBytes
of zero is passed in, this API will function exactly like the nonextended function cudnnBatchNormalizationForwardTraining()
.
This workspace is not required to be clean. Moreover, the workspace does not have to remain unchanged between the forward and backward pass, as it is not used for passing any information.
This extended function can accept a *workspace
pointer to the GPU workspace, and workSpaceSizeInBytes,
the size of the workspace, from the user.
The bnOps
input can be used to set this function to perform either only the batch normalization, or batch normalization followed by activation, or batch normalization followed by elementwise addition and then activation.
Only 4D and 5D tensors are supported. The epsilon
value has to be the same during the training, the backpropagation and the inference.
When the tensor layout is NCHW, higher performance can be obtained when HWpacked tensors are used for x, dy, dx
.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor. See cudnnHandle_t.
 mode

Input. Mode of operation (spatial or peractivation). See cudnnBatchNormMode_t.
 bnOps
 Input. Mode of operation for the fast NHWC kernel. See cudnnBatchNormOps_t.. This input can be used to set this function to perform either only the batch normalization, or batch normalization followed by activation, or batch normalization followed by elementwise addition and then activation.
 *alpha, *beta

Inputs. Pointers to scaling factors (in host memory) used to blend the layer output value with prior value in the destination tensor as follows:
dstValue = alpha[0]*resultValue + beta[0]*priorDstValue.
Refer to this section for additional details.  xDesc, *xData, zDesc, *zData, yDesc, *yData

Tensor descriptors and pointers in device memory for the layer's
x
andy
data, and for the optionalz
tensor input for residual addition to the result of the batch normalization operation, prior to the activation. The optional tensor inputz
should be exact the same size asx
and the final outputy
. Thisz
input is elementwise added to the output of batch normalization. This addition optionally happens after batch normalization and before the activation. See cudnnTensorDescriptor_t.  bnScaleBiasMeanVarDesc

Shared tensor descriptor desc for the secondary tensor that was derived by cudnnDeriveBNTensorDescriptor(). The dimensions for this tensor descriptor are dependent on the normalization mode.
 *bnScaleData, *bnBiasData

Inputs. Pointers in the device memory for the for the batch normalization scale and bias data. In the original paper bias is referred to as beta and scale as gamma. Note that
bnBiasData
parameter can replace the previous operation’s bias parameter for improved efficiency.  exponentialAverageFactor

Input. Factor used in the moving average computation as follows:
runningMean = runningMean*(1factor) + newMean*factor
Use afactor=1/(1+n)
atN
th call to the function to get Cumulative Moving Average (CMA) behavior such that:CMA[n] = (x[1]+...+x[n])/n
. This is proved below: WritingCMA[n+1] = (n*CMA[n]+x[n+1])/(n+1)
= ((n+1)*CMA[n]CMA[n])/(n+1) + x[n+1]/(n+1)
= CMA[n]*(11/(n+1))+x[n+1]*1/(n+1)
= CMA[n]*(1factor) + x(n+1)*factor.
 *resultRunningMeanData, *resultRunningVarianceData

Inputs/Outputs. Pointers to the running mean and running variance data. Both these pointers can be NULL but only at the same time. The value stored in
resultRunningVarianceData
(or passed as an input in inference mode) is the sample variance, and is the moving average of variance[x] where variance is computed either over batch or spatial+batch dimensions depending on the mode. If these pointers are not NULL, the tensors should be initialized to some reasonable values or to 0.  epsilon

Input. Epsilon value used in the batch normalization formula. Minimum allowed value is CUDNN_BN_MIN_EPSILON defined in cudnn.h. Same
epsilon
value should be used in forward and backward functions.  *saveMean, *saveInvVariance

Inputs. Optional cache parameters containing saved intermediate results computed during the forward pass. For this to work correctly, the layer's
x
andbnScaleData
,bnBiasData
data has to remain unchanged until this backward function is called. Note that both these parameters can be NULL but only at the same time. It is recommended to use this cache since the memory overhead is relatively small.  activationDesc

Input. Tensor descriptor for the activation operation. When the
bnOps
input is set to either CUDNN_BATCHNORM_OPS_BN_ACTIVATION or CUDNN_BATCHNORM_OPS_BN_ADD_ACTIVATION then this activation is used.  *workspace, workSpaceSizeInBytes

Inputs.
*workspace
is a pointer to the GPU workspace, andworkSpaceSizeInBytes
is the size of the workspace. When the*workspace
is not NULL and*workSpaceSizeInBytes
is large enough, and the tensor layout is NHWC and the data type configuration is supported, then this function will trigger a new semipersistent NHWC kernel for batch normalization. The workspace is not required to be clean. Also, the workspace does not need to remain unchanged between the forward and backward passes.  *reserveSpace

Input. Pointer to the GPU workspace for the
reserveSpace
.  reserveSpaceSizeInBytes

Input. The size of the
reserveSpace
. Must be equal or larger than the amount required bycudnnGetBatchNormalizationTrainingExReserveSpaceSize()
.
Returns

CUDNN_STATUS_SUCCESS

The computation was performed successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the pointers
alpha, beta, x, y, bnScaleData, bnBiasData
is NULL.  Number of
xDesc
oryDesc
tensor descriptor dimensions is not within the [4,5] range (only 4D and 5D tensors are supported.). bnScaleBiasMeanVarDesc
dimensions are not 1xCx1x1 for 4D and 1xCx1x1x1 for 5D for spatial, and are not 1xCxHxW for 4D and 1xCxDxHxW for 5D for peractivation mode. Exactly one of
saveMean
,saveInvVariance
pointers is NULL.  Exactly one of
resultRunningMeanData
,resultRunningInvVarianceData
pointers is NULL. epsilon
value is less than CUDNN_BN_MIN_EPSILON. Dimensions or data types mismatch for
xDesc
,yDesc
 One of the pointers
4.9. cudnnCTCLoss
cudnnStatus_t cudnnCTCLoss(
cudnnHandle_t handle,
const cudnnTensorDescriptor_t probsDesc,
const void *probs,
const int *labels,
const int *labelLengths,
const int *inputLengths,
void *costs,
const cudnnTensorDescriptor_t gradientsDesc,
const void *gradients,
cudnnCTCLossAlgo_t algo,
const cudnnCTCLossDescriptor_t ctcLossDesc,
void *workspace,
size_t *workSpaceSizeInBytes)
This function returns the ctc costs and gradients, given the probabilities and labels.
Parameters
 handle

Input. Handle to a previously created cuDNN context. See cudnnHandle_t.
 probsDesc

Input. Handle to the previously initialized probabilities tensor descriptor. See cudnnTensorDescriptor_t.
 probs

Input. Pointer to a previously initialized probabilities tensor.
 labels

Input. Pointer to a previously initialized labels list.
 labelLengths

Input. Pointer to a previously initialized lengths list, to walk the above labels list.
 inputLengths

Input. Pointer to a previously initialized list of the lengths of the timing steps in each batch.
 costs

Output. Pointer to the computed costs of CTC.
 gradientsDesc

Input. Handle to a previously initialized gradients tensor descriptor.
 gradients

Output. Pointer to the computed gradients of CTC.
 algo

Input. Enumerant that specifies the chosen CTC loss algorithm. See cudnnCTCLossAlgo_t.
 ctcLossDesc

Input. Handle to the previously initialized CTC loss descriptor. See cudnnCTCLossDescriptor_t.
 workspace

Input. Pointer to GPU memory of a workspace needed to able to execute the specified algorithm.
 sizeInBytes

Input. Amount of GPU memory needed as workspace to be able to execute the CTC loss computation with the specified
algo
.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The dimensions of probsDesc do not match the dimensions of gradientsDesc.
 The inputLengths do not agree with the first dimension of probsDesc.
 The workSpaceSizeInBytes is not sufficient.
 The labelLengths is greater than 256.

CUDNN_STATUS_NOT_SUPPORTED

A compute or data type other than FLOAT was chosen, or an unknown algorithm type was chosen.

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU
4.10. cudnnConvolutionBackwardBias
cudnnStatus_t cudnnConvolutionBackwardBias(
cudnnHandle_t handle,
const void *alpha,
const cudnnTensorDescriptor_t dyDesc,
const void *dy,
const void *beta,
const cudnnTensorDescriptor_t dbDesc,
void *db)
This function computes the convolution function gradient with respect to the bias, which is the sum of every element belonging to the same feature map across all of the images of the input tensor. Therefore, the number of elements produced is equal to the number of features maps of the input tensor.
Parameters
 handle

Input. Handle to a previously created cuDNN context. See cudnnHandle_t.
 alpha, beta

Input. Pointers to scaling factors (in host memory) used to blend the computation result with prior value in the output layer as follows: dstValue = alpha[0]*result + beta[0]*priorDstValue. Refer to this section for additional details.
 dyDesc

Input. Handle to the previously initialized input tensor descriptor. See cudnnTensorDescriptor_t.
 dy

Input. Data pointer to GPU memory associated with the tensor descriptor
dyDesc
.  dbDesc

Input. Handle to the previously initialized output tensor descriptor.
 db

Output. Data pointer to GPU memory associated with the output tensor descriptor
dbDesc
.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The operation was launched successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the parameters
n,height,width
of the output tensor is not 1.  The numbers of feature maps of the input tensor and output tensor differ.
 The
dataType
of the two tensor descriptors are different.
 One of the parameters
4.11. cudnnConvolutionBackwardData
cudnnStatus_t cudnnConvolutionBackwardData(
cudnnHandle_t handle,
const void *alpha,
const cudnnFilterDescriptor_t wDesc,
const void *w,
const cudnnTensorDescriptor_t dyDesc,
const void *dy,
const cudnnConvolutionDescriptor_t convDesc,
cudnnConvolutionBwdDataAlgo_t algo,
void *workSpace,
size_t workSpaceSizeInBytes,
const void *beta,
const cudnnTensorDescriptor_t dxDesc,
void *dx)
This function computes the convolution data gradient of the tensor dy
, where y
is the output of the forward convolution in cudnnConvolutionForward()
. It uses the specified algo
, and returns the results in the output tensor dx
. Scaling factors alpha
and beta
can be used to scale the computed result or accumulate with the current dx
.
Parameters
 handle

Input. Handle to a previously created cuDNN context. See cudnnHandle_t.
 alpha, beta

Input. Pointers to scaling factors (in host memory) used to blend the computation result with prior value in the output layer as follows: dstValue = alpha[0]*result + beta[0]*priorDstValue. Refer to this section for additional details.
 wDesc

Input. Handle to a previously initialized filter descriptor. See cudnnFilterDescriptor_t.
 w

Input. Data pointer to GPU memory associated with the filter descriptor
wDesc
.  dyDesc

Input. Handle to the previously initialized input differential tensor descriptor. See cudnnTensorDescriptor_t.
 dy

Input. Data pointer to GPU memory associated with the input differential tensor descriptor
dyDesc
.  convDesc

Input. Previously initialized convolution descriptor. See cudnnConvolutionDescriptor_t.
 algo

Input. Enumerant that specifies which backward data convolution algorithm shoud be used to compute the results. See cudnnConvolutionBwdDataAlgo_t.
 workSpace

Input. Data pointer to GPU memory to a workspace needed to able to execute the specified algorithm. If no workspace is needed for a particular algorithm, that pointer can be nil.
 workSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
workSpace
.  dxDesc

Input. Handle to the previously initialized output tensor descriptor.
 dx

Input/Output. Data pointer to GPU memory associated with the output tensor descriptor
dxDesc
that carries the result.
TABLE OF THE SUPPORTED CONFIGURATIONS
This function supports the following combinations of data types for wDesc
, dyDesc
, convDesc
, and dxDesc
. See the following table for a list of the supported configurations.
Data Type Configurations  wDesc 's, dyDesc 's and dxDesc 's Data Type 
convDesc 's Data Type 

TRUE_HALF_CONFIG (only supported on architectures with true fp16 support, i.e., compute capability 5.3 and later).  CUDNN_DATA_HALF  CUDNN_DATA_HALF 
PSEUDO_HALF_CONFIG  CUDNN_DATA_HALF  CUDNN_DATA_FLOAT 
FLOAT_CONFIG  CUDNN_DATA_FLOAT  CUDNN_DATA_FLOAT 
DOUBLE_CONFIG  CUDNN_DATA_DOUBLE  CUDNN_DATA_DOUBLE 
Specifying a separate algorithm can cause changes in performance, support and computation determinism. See the following for a list of algorithm options, and their respective supported parameters and deterministic behavior.
TABLE OF THE SUPPORTED ALGORITHMS
The table below shows the list of the supported 2D and 3D convolutions. The 2D convolutions are described first, followed by the 3D convolutions.
For the following terms, the shortform versions shown in the paranthesis are used in the table below, for brevity:
 CUDNN_CONVOLUTION_BWD_DATA_ALGO_0 (_ALGO_0)
 CUDNN_CONVOLUTION_BWD_DATA_ALGO_1 (_ALGO_1)
 CUDNN_CONVOLUTION_BWD_DATA_ALGO_FFT (_FFT)
 CUDNN_CONVOLUTION_BWD_DATA_ALGO_FFT_TILING (_FFT_TILING)
 CUDNN_CONVOLUTION_BWD_DATA_ALGO_WINOGRAD (_WINOGRAD)
 CUDNN_CONVOLUTION_BWD_DATA_ALGO_WINOGRAD_NONFUSED (_WINOGRAD_NONFUSED)
 CUDNN_TENSOR_NCHW (_NCHW)
 CUDNN_TENSOR_NHWC (_NHWC)
 CUDNN_TENSOR_NCHW_VECT_C (_NCHW_VECT_C)
Filter descriptor 

Algo Name (see below for 3D Convolutions) 
Deterministic (Yes or No)  Tensor Formats Supported for
dyDesc 
Tensor Formats Supported for
dxDesc 
Data Type Configurations Supported  Important 
_ALGO_1  NHWC HWCpacked  NHWC HWCpacked   TRUE_HALF_CONFIG,  PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG 

Filter descriptor 

Algo Name  Deterministic (Yes or No)  Tensor Formats Supported for
dyDesc 
Tensor Formats Supported for
dxDesc 
Data Type Configurations Supported  Important 
_ALGO_0  No  NCHW CHWpacked  All except 
 PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG 
 Dilation: greater than 0 for all dimensions  
_ALGO_1  Yes  NCHW CHWpacked  _All except 
 TRUE_HALF_CONFIG,  PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG 
 Dilation: 1 for all dimensions  
_FFT  Yes  NCHW CHWpacked  NCHW HWpacked 
 PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG 
 Dilation: 1 for all dimensions       
_FFT_TILING  Yes  NCHW CHWpacked  NCHW HWpacked 
 PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG  DOUBLE_CONFIG is also supported when the task can be handled by 1D FFT, ie, one of the filter dimension, width or height is 1. 
 Dilation: 1 for all dimensions   When neither of  When either of    
_WINOGRAD  Yes  NCHW CHWpacked  All except 
 PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG 
 Dilation: 1 for all dimensions     
_WINOGRAD_NONFUSED  Yes  NCHW CHWpacked  All except 
 TRUE_HALF_CONFIG,  PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG 
 Dilation: 1 for all dimensions     If 
Filter descriptor 

Algo Name (3D Convolutions)  Deterministic (Yes or No)  Tensor Formats Supported for
dyDesc 
Tensor Formats Supported for
dxDesc 
Data Type Configurations Support  Important 
_ALGO_0  Yes  NCDHW CDHWpacked  All except 
 PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG. 
 Dilation: greater than 0 for all dimensions  
_ALGO_1  Yes  NCDHWfullypacked  NCDHWfullypacked 
 TRUE_HALF_CONFIG,  PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG. 
 Dilation: 1 for all dimensions  
_FFT_TILING  Yes  NCDHW CDHWpacked  NCDHW DHWpacked 
 PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG. 
 Dilation: 1 for all dimensions         
Returns

CUDNN_STATUS_SUCCESS

The operation was launched successfully.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 At least one of the following is NULL:
handle
,dyDesc
,wDesc
,convDesc
,dxDesc
,dy
,w
,dx
,alpha
,beta
wDesc
anddyDesc
have a nonmatching number of dimensionswDesc
anddxDesc
have a nonmatching number of dimensionswDesc
has fewer than three number of dimensionswDesc
,dxDesc
anddyDesc
have a nonmatching data type.wDesc
anddxDesc
have a nonmatching number of input feature maps per image (or group in case of Grouped Convolutions).dyDescs's
spatial sizes do not match with the expected size as determined bycudnnGetConvolutionNdForwardOutputDim
 At least one of the following is NULL:

CUDNN_STATUS_NOT_SUPPORTED

At least one of the following conditions are met:
dyDesc
ordxDesc
have negative tensor stridingdyDesc
,wDesc
ordxDesc
has a number of dimensions that is not 4 or 5 The chosen algo does not support the parameters provided; see above for exhaustive list of parameter support for each algo
dyDesc
orwDesc
indicate an output channel count that isn't a multiple of group count (if group count has been set in convDesc).

CUDNN_STATUS_MAPPING_ERROR

An error occurs during the texture binding of the filter data or the input differential tensor data

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.
4.12. cudnnConvolutionBackwardFilter
cudnnStatus_t cudnnConvolutionBackwardFilter(
cudnnHandle_t handle,
const void *alpha,
const cudnnTensorDescriptor_t xDesc,
const void *x,
const cudnnTensorDescriptor_t dyDesc,
const void *dy,
const cudnnConvolutionDescriptor_t convDesc,
cudnnConvolutionBwdFilterAlgo_t algo,
void *workSpace,
size_t workSpaceSizeInBytes,
const void *beta,
const cudnnFilterDescriptor_t dwDesc,
void *dw)
This function computes the convolution weight (filter) gradient of the tensor dy
, where y
is the output of the forward convolution in cudnnConvolutionForward()
. It uses the specified algo
, and returns the results in the output tensor dw
. Scaling factors alpha
and beta
can be used to scale the computed result or accumulate with the current dw
.
Parameters
 handle

Input. Handle to a previously created cuDNN context. See cudnnHandle_t.
 alpha, beta

Input. Pointers to scaling factors (in host memory) used to blend the computation result with prior value in the output layer as follows: dstValue = alpha[0]*result + beta[0]*priorDstValue. Refer to this section for additional details.
 xDesc

Input. Handle to a previously initialized tensor descriptor. See cudnnTensorDescriptor_t.
 x

Input. Data pointer to GPU memory associated with the tensor descriptor
xDesc
.  dyDesc

Input. Handle to the previously initialized input differential tensor descriptor.
 dy

Input. Data pointer to GPU memory associated with the backpropagation gradient tensor descriptor
dyDesc
.  convDesc

Input. Previously initialized convolution descriptor. See cudnnConvolutionDescriptor_t.
 algo

Input. Enumerant that specifies which convolution algorithm shoud be used to compute the results. See cudnnConvolutionBwdFilterAlgo_t.
 workSpace

Input. Data pointer to GPU memory to a workspace needed to able to execute the specified algorithm. If no workspace is needed for a particular algorithm, that pointer can be nil.
 workSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
workSpace
.  dwDesc

Input. Handle to a previously initialized filter gradient descriptor. See cudnnFilterDescriptor_t.
 dw

Input/Output. Data pointer to GPU memory associated with the filter gradient descriptor
dwDesc
that carries the result.
TABLE OF THE SUPPORTED CONFIGURATIONS
This function supports the following combinations of data types for xDesc
, dyDesc
, convDesc
, and dwDesc
. See the following table for a list of the supported configurations.
Data Type Configurations  xDesc 's, dyDesc 's and dwDesc 's Data Type 
convDesc 's Data Type 

TRUE_HALF_CONFIG (only supported on architectures with true fp16 support, i.e., compute capability 5.3 and later).  CUDNN_DATA_HALF  CUDNN_DATA_HALF 
PSEUDO_HALF_CONFIG  CUDNN_DATA_HALF  CUDNN_DATA_FLOAT 
FLOAT_CONFIG  CUDNN_DATA_FLOAT  CUDNN_DATA_FLOAT 
DOUBLE_CONFIG  CUDNN_DATA_DOUBLE  CUDNN_DATA_DOUBLE 
Specifying a separate algorithm can cause changes in performance, support and computation determinism. See the following for an exhaustive list of algorithm options and their respective supported parameters and deterministic behavior.
TABLE OF THE SUPPORTED ALGORITHMS
The table below shows the list of the supported 2D and 3D convolutions. The 2D convolutions are described first, followed by the 3D convolutions.
For the following terms, the shortform versions shown in the paranthesis are used in the table below, for brevity:
 CUDNN_CONVOLUTION_BWD_FILTER_ALGO_0 (_ALGO_0)
 CUDNN_CONVOLUTION_BWD_FILTER_ALGO_1 (_ALGO_1)
 CUDNN_CONVOLUTION_BWD_FILTER_ALGO_3 (_ALGO_3)
 CUDNN_CONVOLUTION_BWD_FILTER_ALGO_FFT (_FFT)
 CUDNN_CONVOLUTION_BWD_FILTER_ALGO_FFT_TILING (_FFT_TILING)
 CUDNN_CONVOLUTION_BWD_FILTER_ALGO_WINOGRAD_NONFUSED (_WINOGRAD_NONFUSED)
 CUDNN_TENSOR_NCHW (_NCHW)
 CUDNN_TENSOR_NHWC (_NHWC)
 CUDNN_TENSOR_NCHW_VECT_C (_NCHW_VECT_C)
Filter descriptor 

Algo Name (see below for 3D Convolutions) 
Deterministic (Yes or No)  Tensor Formats Supported for
xDesc 
Tensor Formats Supported for
dyDesc 
Data Type Configurations Supported  Important 
_ALGO_0, and _ALGO_1  NHWC HWCpacked  NHWC HWCpacked   PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG 

Filter descriptor 

Algo Name  Deterministic (Yes or No)  Tensor Formats Supported for
xDesc 
Tensor Formats Supported for
dyDesc 
Data Type Configurations Supported  Important 
_ALGO_0  No  All except 
NCHW CHWpacked 
 PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG 
 Dilation: greater than 0 for all dimensions   This algo is not supported if output is of type 
_ALGO_1  Yes  _NCHW or _NHWC 
NCHW CHWpacked 
 TRUE_HALF_CONFIG,  PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG 
 Dilation: 1 for all dimensions  
_FFT  Yes  NCHW CHWpacked 
NCHW CHWpacked 
 PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG 
 Dilation: 1 for all dimensions       
_ALGO_3  Yes  All except 
NCHW CHWpacked 
 PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG 
 Dilation: 1 for all dimensions  
_WINOGRAD_NONFUSED  Yes  All except 
NCHW CHWpacked 
 TRUE_HALF_CONFIG,  PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG 
 Dilation: 1 for all dimensions     If 
_FFT_TILING  Yes  NCHW CHWpacked 
NCHW CHWpacked 
 PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG 
 Dilation: 1 for all dimensions       
Filter descriptor 

Algo Name  Deterministic (Yes or No)  Tensor Formats Supported for
xDesc 
Tensor Formats Supported for
dyDesc 
Data Type Configurations Support  Important 
_ALGO_0  No  All except 
NCDHW CDHWpacked 
 PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG. 
 Dilation: greater than 0 for all dimensions  
_ALGO_3  No  NCDHWfullypacked 
NCDHWfullypacked 
 PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG. 
 Dilation: 1 for all dimensions  
Returns

CUDNN_STATUS_SUCCESS

The operation was launched successfully.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 At least one of the following is NULL:
handle
,xDesc
,dyDesc
,convDesc
,dwDesc
,xData
,dyData
,dwData
,alpha
,beta
xDesc
anddyDesc
have a nonmatching number of dimensionsxDesc
anddwDesc
have a nonmatching number of dimensionsxDesc
has fewer than three number of dimensionsxDesc
,dyDesc
anddwDesc
have a nonmatching data type.xDesc
anddwDesc
have a nonmatching number of input feature maps per image (or group in case of Grouped Convolutions).yDesc
orwDesc
indicate an output channel count that isn't a multiple of group count (if group count has been set in convDesc).
 At least one of the following is NULL:

CUDNN_STATUS_NOT_SUPPORTED

At least one of the following conditions are met:
xDesc
ordyDesc
have negative tensor stridingxDesc
,dyDesc
ordwDesc
has a number of dimensions that is not 4 or 5 The chosen algo does not support the parameters provided; see above for exhaustive list of parameter support for each algo

CUDNN_STATUS_MAPPING_ERROR

An error occurs during the texture binding of the filter data.

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.
4.13. cudnnConvolutionBiasActivationForward
cudnnStatus_t cudnnConvolutionBiasActivationForward(
cudnnHandle_t handle,
const void *alpha1,
const cudnnTensorDescriptor_t xDesc,
const void *x,
const cudnnFilterDescriptor_t wDesc,
const void *w,
const cudnnConvolutionDescriptor_t convDesc,
cudnnConvolutionFwdAlgo_t algo,
void *workSpace,
size_t workSpaceSizeInBytes,
const void *alpha2,
const cudnnTensorDescriptor_t zDesc,
const void *z,
const cudnnTensorDescriptor_t biasDesc,
const void *bias,
const cudnnActivationDescriptor_t activationDesc,
const cudnnTensorDescriptor_t yDesc,
void *y)
This function applies a bias and then an activation to the convolutions or crosscorrelations of cudnnConvolutionForward(), returning results in y
. The full computation follows the equation y = act ( alpha1 * conv(x) + alpha2 * z + bias )
.
The routine cudnnGetConvolution2dForwardOutputDim
or cudnnGetConvolutionNdForwardOutputDim
can be used to determine the proper dimensions of the output tensor descriptor yDesc
with respect to xDesc
, convDesc
and wDesc
.
Only the CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_PRECOMP_GEMM algo is enabled with CUDNN_ACTIVATION_IDENTITY. In other words, in the cudnnActivationDescriptor_t
structure of the input activationDesc
, if the mode of the cudnnActivationMode_t
field is set to the enum value CUDNN_ACTIVATION_IDENTITY, then the input cudnnConvolutionFwdAlgo_t
of this function cudnnConvolutionBiasActivationForward()
must be set to the enum value CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_PRECOMP_GEMM. See also the documentation for the function cudnnSetActivationDescriptor()
.
Parameters
 handle

Input. Handle to a previously created cuDNN context. See cudnnHandle_t.
 alpha1, alpha2

Input. Pointers to scaling factors (in host memory) used to blend the computation result with prior value in the output layer as described by the above equation. Please refer to this section for additional details.
 xDesc

Input. Handle to a previously initialized tensor descriptor. See cudnnTensorDescriptor_t.
 x

Input. Data pointer to GPU memory associated with the tensor descriptor
xDesc
.  wDesc

Input. Handle to a previously initialized filter descriptor. See cudnnFilterDescriptor_t.
 w

Input. Data pointer to GPU memory associated with the filter descriptor
wDesc
.  convDesc

Input. Previously initialized convolution descriptor. See cudnnConvolutionDescriptor_t.
 algo

Input. Enumerant that specifies which convolution algorithm should be used to compute the results. See cudnnConvolutionFwdAlgo_t.
 workSpace

Input. Data pointer to GPU memory to a workspace needed to able to execute the specified algorithm. If no workspace is needed for a particular algorithm, that pointer can be nil.
 workSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
workSpace
.  zDesc

Input. Handle to a previously initialized tensor descriptor.
 z

Input. Data pointer to GPU memory associated with the tensor descriptor
zDesc
.  biasDesc

Input. Handle to a previously initialized tensor descriptor.
 bias

Input. Data pointer to GPU memory associated with the tensor descriptor
biasDesc
.  activationDesc

Input. Handle to a previously initialized activation descriptor. See cudnnActivationDescriptor_t.
 yDesc

Input. Handle to a previously initialized tensor descriptor.
 y

Input/Output. Data pointer to GPU memory associated with the tensor descriptor
yDesc
that carries the result of the convolution.
For the convolution step, this function supports the specific combinations of data types for xDesc
, wDesc
, convDesc
and yDesc
as listed in the documentation of cudnnConvolutionForward(). The following table specifies the supported combinations of data types for x
, y
, z
, bias
, and alpha1/alpha2
.
x  w  y and z  bias  alpha1/alpha2 

X_DOUBLE  X_DOUBLE  X_DOUBLE  X_DOUBLE  X_DOUBLE 
X_FLOAT  X_FLOAT  X_FLOAT  X_FLOAT  X_FLOAT 
X_HALF  X_HALF  X_HALF  X_HALF  X_FLOAT 
X_INT8  X_INT8  X_INT8  X_FLOAT  X_FLOAT 
X_INT8  X_INT8  X_FLOAT  X_FLOAT  X_FLOAT 
X_INT8x4  X_INT8x4  X_INT8x4  X_FLOAT  X_FLOAT 
X_INT8x4  X_INT8x4  X_FLOAT  X_FLOAT  X_FLOAT 
X_UINT8  X_INT8  X_INT8  X_FLOAT  X_FLOAT 
X_UINT8  X_INT8  X_FLOAT  X_FLOAT  X_FLOAT 
X_UINT8x4  X_INT8x4  X_INT8x4  X_FLOAT  X_FLOAT 
X_UINT8x4  X_INT8x4  X_FLOAT  X_FLOAT  X_FLOAT 
In addition to the error values listed by the documentation of cudnnConvolutionForward(), the possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The operation was launched successfully.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 At least one of the following is NULL:
zDesc
,zData
,biasDesc
,bias
,activationDesc
.  The second dimension of
biasDesc
and the first dimension offilterDesc
are not equal. zDesc
anddestDesc
do not match.
 At least one of the following is NULL:

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration. See the following for some examples of nonsupported configurations:
 The
mode
ofactivationDesc
is neitherCUDNN_ACTIVATION_RELU
orCUDNN_ACTIVATION_IDENTITY
.  The
reluNanOpt
ofactivationDesc
is notCUDNN_NOT_PROPAGATE_NAN
.  The second stride of
biasDesc
is not equal to one.  The data type of
biasDesc
does not correspond to the data type ofyDesc
as listed in the above data types table.
 The

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.
4.14. cudnnConvolutionForward
cudnnStatus_t cudnnConvolutionForward(
cudnnHandle_t handle,
const void *alpha,
const cudnnTensorDescriptor_t xDesc,
const void *x,
const cudnnFilterDescriptor_t wDesc,
const void *w,
const cudnnConvolutionDescriptor_t convDesc,
cudnnConvolutionFwdAlgo_t algo,
void *workSpace,
size_t workSpaceSizeInBytes,
const void *beta,
const cudnnTensorDescriptor_t yDesc,
void *y)
This function executes convolutions or crosscorrelations over x
using filters specified with w
, returning results in y
. Scaling factors alpha
and beta
can be used to scale the input tensor and the output tensor respectively.
The routine cudnnGetConvolution2dForwardOutputDim
or cudnnGetConvolutionNdForwardOutputDim
can be used to determine the proper dimensions of the output tensor descriptor yDesc
with respect to xDesc
, convDesc
and wDesc
.
Parameters
 handle

Input. Handle to a previously created cuDNN context. See cudnnHandle_t.
 alpha, beta

Input. Pointers to scaling factors (in host memory) used to blend the computation result with prior value in the output layer as follows: dstValue = alpha[0]*result + beta[0]*priorDstValue. Refer to this section for additional details.
 xDesc

Input. Handle to a previously initialized tensor descriptor. See cudnnTensorDescriptor_t.
 x

Input. Data pointer to GPU memory associated with the tensor descriptor
xDesc
.  wDesc

Input. Handle to a previously initialized filter descriptor. See cudnnFilterDescriptor_t.
 w

Input. Data pointer to GPU memory associated with the filter descriptor
wDesc
.  convDesc

Input. Previously initialized convolution descriptor. See cudnnConvolutionDescriptor_t.
 algo

Input. Enumerant that specifies which convolution algorithm shoud be used to compute the results. See cudnnConvolutionFwdAlgo_t.
 workSpace

Input. Data pointer to GPU memory to a workspace needed to able to execute the specified algorithm. If no workspace is needed for a particular algorithm, that pointer can be nil.
 workSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
workSpace
.  yDesc

Input. Handle to a previously initialized tensor descriptor.
 y

Input/Output. Data pointer to GPU memory associated with the tensor descriptor
yDesc
that carries the result of the convolution.
TABLE OF THE SUPPORTED CONFIGURATIONS
This function supports the following combinations of data types for xDesc
, wDesc
, convDesc
, and yDesc
. See the following table for a list of the supported configurations.
Data Type Configurations  xDesc and wDesc 
convDesc 
yDesc 

TRUE_HALF_CONFIG (only supported on architectures with true fp16 support, i.e., compute capability 5.3 and later).  CUDNN_DATA_HALF  CUDNN_DATA_HALF  CUDNN_DATA_HALF 
PSEUDO_HALF_CONFIG  CUDNN_DATA_HALF  CUDNN_DATA_FLOAT  CUDNN_DATA_HALF 
FLOAT_CONFIG  CUDNN_DATA_FLOAT  CUDNN_DATA_FLOAT  CUDNN_DATA_FLOAT 
DOUBLE_CONFIG  CUDNN_DATA_DOUBLE  CUDNN_DATA_DOUBLE  CUDNN_DATA_DOUBLE 
INT8_CONFIG (only supported on architectures with DP4A support, i.e., compute capability 6.1 and later).  CUDNN_DATA_INT8  CUDNN_DATA_INT32  CUDNN_DATA_INT8 
INT8_EXT_CONFIG (only supported on architectures with DP4A support, i.e., compute capability 6.1 and later).  CUDNN_DATA_INT8  CUDNN_DATA_INT32  CUDNN_DATA_FLOAT 
INT8x4_CONFIG (only supported on architectures with DP4A support, i.e., compute capability 6.1 and later).  CUDNN_DATA_INT8x4  CUDNN_DATA_INT32  CUDNN_DATA_INT8x4 
INT8x4_EXT_CONFIG (only supported on architectures with DP4A support, i.e., compute capability 6.1 and later).  CUDNN_DATA_INT8x4  CUDNN_DATA_INT32  CUDNN_DATA_FLOAT 
UINT8x4_CONFIG (new for 7.1) (only supported on architectures with DP4A support, i.e., compute capability 6.1 and later).  CUDNN_DATA_UINT8x4  CUDNN_DATA_INT32  CUDNN_DATA_UINT8x4 
UINT8x4_EXT_CONFIG (new for 7.1) (only supported on architectures with DP4A support, i.e., compute capability 6.1 and later).  CUDNN_DATA_UINT8x4  CUDNN_DATA_INT32  CUDNN_DATA_FLOAT 
For this function, all algorithms perform deterministic computations. Specifying a separate algorithm can cause changes in performance and support.
TABLE OF THE SUPPORTED ALGORITHMS
The table below shows the list of the supported 2D and 3D convolutions. The 2D convolutions are described first, followed by the 3D convolutions.
For the following terms, the shortform versions shown in the paranthesis are used in the table below, for brevity:
 CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_GEMM (_IMPLICIT_GEMM)
 CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_PRECOMP_GEMM (_IMPLICIT_PRECOMP_GEMM)
 CUDNN_CONVOLUTION_FWD_ALGO_GEMM (_GEMM)
 CUDNN_CONVOLUTION_FWD_ALGO_DIRECT (_DIRECT)
 CUDNN_CONVOLUTION_FWD_ALGO_FFT (_FFT)
 CUDNN_CONVOLUTION_FWD_ALGO_FFT_TILING (_FFT_TILING)
 CUDNN_CONVOLUTION_FWD_ALGO_WINOGRAD (_WINOGRAD)
 CUDNN_CONVOLUTION_FWD_ALGO_WINOGRAD_NONFUSED (_WINOGRAD_NONFUSED)
 CUDNN_TENSOR_NCHW (_NCHW)
 CUDNN_TENSOR_NHWC (_NHWC)
 CUDNN_TENSOR_NCHW_VECT_C (_NCHW_VECT_C)
Filter descriptor


Algo Name (see below for 3D Convolutions) 
Tensor Formats Supported for
xDesc 
Tensor Formats Supported for
yDesc 
Data Type Configurations Supported  Important 
_IMPLICIT_GEMM  All except _NCHW_VECT_C . 
All except _NCHW_VECT_C . 
 PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG 
Dilation: Greater than 0 for all dimensions. 
_IMPLICIT_PRECOMP_GEMM   TRUE_HALF_CONFIG,  PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG. 
Dilation: 1 for all dimensions. 

_GEMM   PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG 
Dilation: 1 for all dimensions. 

_FFT  NCHW HWpacked  NCHW HWpacked   PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG 
Dilation: 1 for all dimensions.  xDesc's feature map height + 2 * convDesc's zeropadding height must equal 256 or less  xDesc's feature map width + 2 * convDesc's zeropadding width must equal 256 or less  convDesc's vertical and horizontal filter stride must equal 1  wDesc's filter height must be greater than convDesc's zeropadding height  wDesc's filter width must be greater than convDesc's zeropadding width 
_FFT_TILING   PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG DOUBLE_CONFIG is also supported when the task can be handled by 1D FFT, i.e., one of the filter dimension, width or height is 1. 
Dilation: 1 for all dimensions.  When neither of wDesc's filter dimension is 1, the filter width and height must not be larger than 32  When either of wDesc's filter dimension is 1, the largest filter dimension should not exceed 256  convDesc's vertical and horizontal filter stride must equal 1 when either the filter width or filter height is 1, otherwise the stride can be 1 or 2  wDesc's filter height must be greater than convDesc's zeropadding height  wDesc's filter width must be greater than convDesc's zeropadding width 

_WINOGRAD  All except: _NCHW_VECT_C  All except: _NCHW_VECT_C   PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG 
Dilation: 1 for all dimensions.  convDesc's vertical and horizontal filter stride must equal 1  wDesc's filter height must be 3  wDesc's filter width must be 3 
_WINOGRAD_NONFUSED   TRUE_HALF_CONFIG,  PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG 
Dilation: 1 for all dimensions.  convDesc's vertical and horizontal filter stride must equal 1  wDesc's filter (height, width) must be (3,3) or (5,5)  If wDesc's filter (height, width) is (5,5), then data type config TRUE_HALF_CONFIG is not supported 

_DIRECT  Currently not implemented in cuDNN.  
Filter descriptor


Algo Name 
xDesc 
yDesc 
Data Type Configurations Support  Important 
_IMPLICIT_GEMM  NCHWC HWCpacked  NCHWC HWCpacked   PSEUDO_HALF_CONFIG, and  FLOAT_CONFIG 
Dilation: Greater than 0 for all dimensions. 
Filter descriptor


Algo Name 
xDesc 
yDesc 
Data Type Configurations Support  Important 
_IMPLICIT_PRECOMP_GEMM  NHWC  NHWC   INT8_CONFIG,  INT8_EXT_CONFIG,  INT8x4_CONFIG,  INT8x4_EXT_CONFIG,  UINT8x4_CONFIG, and  UINT8x4_EXT_CONFIG 
Dilation: 1 for all dimensions. Input and output features maps must be multiple of 4. 
Filter descriptor convDesc Group count support: Greater than 0, for all algos. 

Algo Name 
xDesc 
yDesc 
Data Type Configurations Support  Important 
_IMPLICIT_GEMM  All except _NCHW_VECT_C . 
All except _NCHW_VECT_C . 
 PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG. 
Dilation: Greater than 0 for all dimensions. 
_IMPLICIT_PRECOMP_GEMM  Dilation: 1 for all dimensions. 

_FFT_TILING  NCDHW DHWpacked  NCDHW DHWpacked   PSEUDO_HALF_CONFIG,  FLOAT_CONFIG, and  DOUBLE_CONFIG. 
Dilation: 1 for all dimensions.        
Tensors can be converted to, and from, CUDNN_TENSOR_NCHW_VECT_C with cudnnTransformTensor().
Returns

CUDNN_STATUS_SUCCESS

The operation was launched successfully.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 At least one of the following is NULL: handle,
xDesc
,wDesc
,convDesc
,yDesc
,xData
,w
,yData
,alpha
,beta
xDesc
andyDesc
have a nonmatching number of dimensionsxDesc
andwDesc
have a nonmatching number of dimensionsxDesc
has fewer than three number of dimensionsxDesc
's number of dimensions is not equal toconvDesc
's array length + 2xDesc
andwDesc
have a nonmatching number of input feature maps per image (or group in case of Grouped Convolutions)yDesc
orwDesc
indicate an output channel count that isn't a multiple of group count (if group count has been set in convDesc).xDesc
,wDesc
andyDesc
have a nonmatching data type For some spatial dimension,
wDesc
has a spatial size that is larger than the input spatial size (including zeropadding size)
 At least one of the following is NULL: handle,

CUDNN_STATUS_NOT_SUPPORTED

At least one of the following conditions are met:
xDesc
oryDesc
have negative tensor stridingxDesc
,wDesc
oryDesc
has a number of dimensions that is not 4 or 5yDescs's
spatial sizes do not match with the expected size as determined bycudnnGetConvolutionNdForwardOutputDim
 The chosen algo does not support the parameters provided; see above for exhaustive list of parameter support for each algo

CUDNN_STATUS_MAPPING_ERROR

An error occured during the texture binding of the filter data.

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.
4.15. cudnnCreate
cudnnStatus_t cudnnCreate(cudnnHandle_t *handle)
This function initializes the cuDNN library and creates a handle to an opaque structure holding the cuDNN library context. It allocates hardware resources on the host and device and must be called prior to making any other cuDNN library calls.
The cuDNN library handle is tied to the current CUDA device (context). To use the library on multiple devices, one cuDNN handle needs to be created for each device.
For a given device, multiple cuDNN handles with different configurations (e.g., different current CUDA streams) may be created. Because cudnnCreate
allocates some internal resources, the release of those resources by calling cudnnDestroy
will implicitly call cudaDeviceSynchronize
; therefore, the recommended best practice is to call cudnnCreate/cudnnDestroy
outside of performancecritical code paths.
For multithreaded applications that use the same device from different threads, the recommended programming model is to create one (or a few, as is convenient) cuDNN handle(s) per thread and use that cuDNN handle for the entire life of the thread.
Parameters
 handle

Output. Pointer to pointer where to store the address to the allocated cuDNN handle. See cudnnHandle_t.
Returns

CUDNN_STATUS_BAD_PARAM

Invalid (NULL) input pointer supplied.

CUDNN_STATUS_NOT_INITIALIZED

No compatible GPU found, CUDA driver not installed or disabled, CUDA runtime API initialization failed.

CUDNN_STATUS_ARCH_MISMATCH

NVIDIA GPU architecture is too old.

CUDNN_STATUS_ALLOC_FAILED

Host memory allocation failed.

CUDNN_STATUS_INTERNAL_ERROR

CUDA resource allocation failed.

CUDNN_STATUS_LICENSE_ERROR

cuDNN license validation failed (only when the feature is enabled).

CUDNN_STATUS_SUCCESS

cuDNN handle was created successfully.
4.16. cudnnCreateActivationDescriptor
cudnnStatus_t cudnnCreateActivationDescriptor(
cudnnActivationDescriptor_t *activationDesc)
This function creates a activation descriptor object by allocating the memory needed to hold its opaque structure. See cudnnActivationDescriptor_t.
Returns

CUDNN_STATUS_SUCCESS

The object was created successfully.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.
4.17. cudnnCreateAlgorithmDescriptor
cudnnStatus_t cudnnCreateAlgorithmDescriptor(
cudnnAlgorithmDescriptor_t *algoDesc)
(New for 7.1)
This function creates an algorithm descriptor object by allocating the memory needed to hold its opaque structure.
Returns

CUDNN_STATUS_SUCCESS

The object was created successfully.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.
4.18. cudnnCreateAlgorithmPerformance
cudnnStatus_t cudnnCreateAlgorithmPerformance(
cudnnAlgorithmPerformance_t *algoPerf,
int numberToCreate)
(New for 7.1)
This function creates multiple algorithm performance objects by allocating the memory needed to hold their opaque structures.
Returns

CUDNN_STATUS_SUCCESS

The object was created successfully.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.
4.19. cudnnCreateCTCLossDescriptor
cudnnStatus_t cudnnCreateCTCLossDescriptor(
cudnnCTCLossDescriptor_t* ctcLossDesc)
This function creates a CTC loss function descriptor. .
Parameters
 ctcLossDesc

Output. CTC loss descriptor to be set. See cudnnCTCLossDescriptor_t.
Returns

CUDNN_STATUS_SUCCESS

The function returned successfully.

CUDNN_STATUS_BAD_PARAM

CTC loss descriptor passed to the function is invalid.

CUDNN_STATUS_ALLOC_FAILED

Memory allocation for this CTC loss descriptor failed.
4.20. cudnnCreateConvolutionDescriptor
cudnnStatus_t cudnnCreateConvolutionDescriptor(
cudnnConvolutionDescriptor_t *convDesc)
This function creates a convolution descriptor object by allocating the memory needed to hold its opaque structure. See cudnnConvolutionDescriptor_t.
Returns

CUDNN_STATUS_SUCCESS

The object was created successfully.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.
4.21. cudnnCreateDropoutDescriptor
cudnnStatus_t cudnnCreateDropoutDescriptor(
cudnnDropoutDescriptor_t *dropoutDesc)
This function creates a generic dropout descriptor object by allocating the memory needed to hold its opaque structure. See cudnnDropoutDescriptor_t.
Returns

CUDNN_STATUS_SUCCESS

The object was created successfully.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.
4.22. cudnnCreateFilterDescriptor
cudnnStatus_t cudnnCreateFilterDescriptor(
cudnnFilterDescriptor_t *filterDesc)
This function creates a filter descriptor object by allocating the memory needed to hold its opaque structure. See cudnnFilterDescriptor_t.
Returns

CUDNN_STATUS_SUCCESS

The object was created successfully.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.
4.23. cudnnCreateLRNDescriptor
cudnnStatus_t cudnnCreateLRNDescriptor(
cudnnLRNDescriptor_t *poolingDesc)
This function allocates the memory needed to hold the data needed for LRN and DivisiveNormalization layers operation and returns a descriptor used with subsequent layer forward and backward calls.
Returns

CUDNN_STATUS_SUCCESS

The object was created successfully.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.
cudnnCreateOpTensorDescriptor
cudnnStatus_t cudnnCreateOpTensorDescriptor(
cudnnOpTensorDescriptor_t* opTensorDesc)
This function creates a Tensor Pointwise math descriptor. See cudnnOpTensorDescriptor_t.
Parameters
 opTensorDesc

Output. Pointer to the structure holding the description of the Tensor Pointwise math such as Add, Multiply, and more.
Returns

CUDNN_STATUS_SUCCESS

The function returned successfully.

CUDNN_STATUS_BAD_PARAM

Tensor Pointwise math descriptor passed to the function is invalid.

CUDNN_STATUS_ALLOC_FAILED

Memory allocation for this Tensor Pointwise math descriptor failed.
4.25. cudnnCreatePersistentRNNPlan
cudnnStatus_t cudnnCreatePersistentRNNPlan(
cudnnRNNDescriptor_t rnnDesc,
const int minibatch,
const cudnnDataType_t dataType,
cudnnPersistentRNNPlan_t *plan)
This function creates a plan to execute persistent RNNs when using the CUDNN_RNN_ALGO_PERSIST_DYNAMIC
algo. This plan is tailored to the current GPU and problem hyperparemeters. This function call is expected to be expensive in terms of runtime, and should be used infrequently. See cudnnRNNDescriptor_t, cudnnDataType_t, and cudnnPersistentRNNPlan_t.
Returns

CUDNN_STATUS_SUCCESS

The object was created successfully.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.

CUDNN_STATUS_RUNTIME_PREREQUISITE_MISSING

A prerequisite runtime library cannot be found.

CUDNN_STATUS_NOT_SUPPORTED

The current hyperparameters are invalid.
4.26. cudnnCreatePoolingDescriptor
cudnnStatus_t cudnnCreatePoolingDescriptor(
cudnnPoolingDescriptor_t *poolingDesc)
This function creates a pooling descriptor object by allocating the memory needed to hold its opaque structure,
Returns

CUDNN_STATUS_SUCCESS

The object was created successfully.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.
4.27. cudnnCreateRNNDescriptor
cudnnStatus_t cudnnCreateRNNDescriptor(
cudnnRNNDescriptor_t *rnnDesc)
This function creates a generic RNN descriptor object by allocating the memory needed to hold its opaque structure.
Returns

CUDNN_STATUS_SUCCESS

The object was created successfully.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.
4.28. cudnnCreateRNNDataDescriptor
cudnnStatus_t cudnnCreateRNNDataDescriptor(
cudnnRNNDataDescriptor_t *RNNDataDesc)
This function creates a RNN data descriptor object by allocating the memory needed to hold its opaque structure.
Returns

CUDNN_STATUS_SUCCESS

The RNN data descriptor object was created successfully.

CUDNN_STATUS_BAD_PARAM

RNNDataDesc is NULL.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.
4.29. cudnnCreateReduceTensorDescriptor
cudnnStatus_t cudnnCreateReduceTensorDescriptor(
cudnnReduceTensorDescriptor_t* reduceTensorDesc)
This function creates a reduce tensor descriptor object by allocating the memory needed to hold its opaque structure.
Parameters
None.
Returns

CUDNN_STATUS_SUCCESS

The object was created successfully.

CUDNN_STATUS_BAD_PARAM

reduceTensorDesc is a NULL pointer.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.
4.30. cudnnCreateSpatialTransformerDescriptor
cudnnStatus_t cudnnCreateSpatialTransformerDescriptor(
cudnnSpatialTransformerDescriptor_t *stDesc)
This function creates a generic spatial transformer descriptor object by allocating the memory needed to hold its opaque structure.
Returns

CUDNN_STATUS_SUCCESS

The object was created successfully.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.
4.31. cudnnCreateTensorDescriptor
cudnnStatus_t cudnnCreateTensorDescriptor(
cudnnTensorDescriptor_t *tensorDesc)
This function creates a generic tensor descriptor object by allocating the memory needed to hold its opaque structure. The data is initialized to be all zero.
Parameters
 tensorDesc

Input. Pointer to pointer where the address to the allocated tensor descriptor object should be stored.
Returns

CUDNN_STATUS_BAD_PARAM

Invalid input argument.

CUDNN_STATUS_ALLOC_FAILED

The resources could not be allocated.

CUDNN_STATUS_SUCCESS

The object was created successfully.
4.32. cudnnDeriveBNTensorDescriptor
cudnnStatus_t cudnnDeriveBNTensorDescriptor(
cudnnTensorDescriptor_t derivedBnDesc,
const cudnnTensorDescriptor_t xDesc,
cudnnBatchNormMode_t mode)
This function derives a secondary tensor descriptor for the batch normalization scale, invVariance, bnBias, bnScale subtensors from the layer's x
data descriptor.
Use the tensor descriptor produced by this function as the bnScaleBiasMeanVarDesc
parameter for the cudnnBatchNormalizationForwardInference
and cudnnBatchNormalizationForwardTraining
functions, and as the bnScaleBiasDiffDesc
parameter in the cudnnBatchNormalizationBackward
function.
The resulting dimensions will be 1xCx1x1 for 4D and 1xCx1x1x1 for 5D for BATCHNORM_MODE_SPATIAL, and 1xCxHxW for 4D and 1xCxDxHxW for 5D for BATCHNORM_MODE_PER_ACTIVATION mode.
For HALF input data type the resulting tensor descriptor will have a FLOAT type. For other data types it will have the same type as the input data.
Only 4D and 5D tensors are supported.
The derivedBnDesc
should be first created using cudnnCreateTensorDescriptor
.
xDesc
is the descriptor for the layer's x
data and has to be setup with proper dimensions prior to calling this function.
Parameters
 derivedBnDesc

Output. Handle to a previously created tensor descriptor.
 xDesc

Input. Handle to a previously created and initialized layer's
x
data descriptor.  mode

Input. Batch normalization layer mode of operation.
Returns

CUDNN_STATUS_SUCCESS

The computation was performed successfully.

CUDNN_STATUS_BAD_PARAM
 Invalid Batch Normalization mode.
4.33. cudnnDestroy
cudnnStatus_t cudnnDestroy(cudnnHandle_t handle)
This function releases resources used by the cuDNN handle. This function is usually the last call with a particular handle to the cuDNN handle. Because cudnnCreate
allocates some internal resources, the release of those resources by calling cudnnDestroy
will implicitly call cudaDeviceSynchronize
; therefore, the recommended best practice is to call cudnnCreate/cudnnDestroy
outside of performancecritical code paths.
Parameters
 handle

Input. Pointer to the cuDNN handle to be destroyed.
Returns

CUDNN_STATUS_SUCCESS

The cuDNN context destruction was successful.

CUDNN_STATUS_BAD_PARAM

Invalid (NULL) pointer supplied.
4.34. cudnnDestroyActivationDescriptor
cudnnStatus_t cudnnDestroyActivationDescriptor(
cudnnActivationDescriptor_t activationDesc)
This function destroys a previously created activation descriptor object.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.35. cudnnDestroyAlgorithmDescriptor
cudnnStatus_t cudnnDestroyAlgorithmDescriptor(
cudnnActivationDescriptor_t algorithmDesc)
(New for 7.1)
This function destroys a previously created algorithm descriptor object.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.36. cudnnDestroyAlgorithmPerformance
cudnnStatus_t cudnnDestroyAlgorithmPerformance(
cudnnAlgorithmPerformance_t algoPerf)
(New for 7.1)
This function destroys a previously created algorithm descriptor object.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.37. cudnnDestroyCTCLossDescriptor
cudnnStatus_t cudnnDestroyCTCLossDescriptor(
cudnnCTCLossDescriptor_t ctcLossDesc)
This function destroys a CTC loss function descriptor object.
Parameters
 ctcLossDesc

Input. CTC loss function descriptor to be destroyed.
Returns

CUDNN_STATUS_SUCCESS

The function returned successfully.
4.38. cudnnDestroyConvolutionDescriptor
cudnnStatus_t cudnnDestroyConvolutionDescriptor(
cudnnConvolutionDescriptor_t convDesc)
This function destroys a previously created convolution descriptor object.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.39. cudnnDestroyDropoutDescriptor
cudnnStatus_t cudnnDestroyDropoutDescriptor(
cudnnDropoutDescriptor_t dropoutDesc)
This function destroys a previously created dropout descriptor object.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.40. cudnnDestroyFilterDescriptor
cudnnStatus_t cudnnDestroyFilterDescriptor(
cudnnFilterDescriptor_t filterDesc)
This function destroys a previously created Tensor4D descriptor object.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.41. cudnnDestroyLRNDescriptor
cudnnStatus_t cudnnDestroyLRNDescriptor(
cudnnLRNDescriptor_t lrnDesc)
This function destroys a previously created LRN descriptor object.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.42. cudnnDestroyOpTensorDescriptor
cudnnStatus_t cudnnDestroyOpTensorDescriptor(
cudnnOpTensorDescriptor_t opTensorDesc)
This function deletes a Tensor Pointwise math descriptor object.
Parameters
 opTensorDesc

Input. Pointer to the structure holding the description of the Tensor Pointwise math to be deleted.
Returns

CUDNN_STATUS_SUCCESS

The function returned successfully.
4.43. cudnnDestroyPersistentRNNPlan
cudnnStatus_t cudnnDestroyPersistentRNNPlan(
cudnnPersistentRNNPlan_t plan)
This function destroys a previously created persistent RNN plan object.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.44. cudnnDestroyPoolingDescriptor
cudnnStatus_t cudnnDestroyPoolingDescriptor(
cudnnPoolingDescriptor_t poolingDesc)
This function destroys a previously created pooling descriptor object.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.45. cudnnDestroyRNNDescriptor
cudnnStatus_t cudnnDestroyRNNDescriptor(
cudnnRNNDescriptor_t rnnDesc)
This function destroys a previously created RNN descriptor object.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.46. cudnnDestroyRNNDataDescriptor
cudnnStatus_t cudnnDestroyRNNDataDescriptor(
cudnnRNNDataDescriptor_t RNNDataDesc)
This function destroys a previously created RNN data descriptor object.
Returns

CUDNN_STATUS_SUCCESS

The RNN data descriptor object was destroyed successfully.
4.47. cudnnDestroyReduceTensorDescriptor
cudnnStatus_t cudnnDestroyReduceTensorDescriptor(
cudnnReduceTensorDescriptor_t tensorDesc)
This function destroys a previously created reduce tensor descriptor object. When the input pointer is NULL, this function performs no destroy operation.
Parameters
 tensorDesc

Input. Pointer to the reduce tensor descriptor object to be destroyed.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.48. cudnnDestroySpatialTransformerDescriptor
cudnnStatus_t cudnnDestroySpatialTransformerDescriptor(
cudnnSpatialTransformerDescriptor_t stDesc)
This function destroys a previously created spatial transformer descriptor object.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.49. cudnnDestroyTensorDescriptor
cudnnStatus_t cudnnDestroyTensorDescriptor(cudnnTensorDescriptor_t tensorDesc)
This function destroys a previously created tensor descriptor object. When the input pointer is NULL, this function performs no destroy operation.
Parameters
 tensorDesc

Input. Pointer to the tensor descriptor object to be destroyed.
Returns

CUDNN_STATUS_SUCCESS

The object was destroyed successfully.
4.50. cudnnDivisiveNormalizationBackward
cudnnStatus_t cudnnDivisiveNormalizationBackward(
cudnnHandle_t handle,
cudnnLRNDescriptor_t normDesc,
cudnnDivNormMode_t mode,
const void *alpha,
const cudnnTensorDescriptor_t xDesc,
const void *x,
const void *means,
const void *dy,
void *temp,
void *temp2,
const void *beta,
const cudnnTensorDescriptor_t dxDesc,
void *dx,
void *dMeans)
This function performs the backward DivisiveNormalization layer computation.
Supported tensor formats are NCHW for 4D and NCDHW for 5D with any nonoverlapping nonnegative strides. Only 4D and 5D tensors are supported.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor.
 normDesc

Input. Handle to a previously intialized LRN parameter descriptor (this descriptor is used for both LRN and DivisiveNormalization layers).
 mode

Input. DivisiveNormalization layer mode of operation. Currently only CUDNN_DIVNORM_PRECOMPUTED_MEANS is implemented. Normalization is performed using the means input tensor that is expected to be precomputed by the user.
 alpha, beta

Input. Pointers to scaling factors (in host memory) used to blend the layer output value with prior value in the destination tensor as follows: dstValue = alpha[0]*resultValue + beta[0]*priorDstValue. Please refer to this section for additional details.
 xDesc, x, means

Input. Tensor descriptor and pointers in device memory for the layer's x and means data. Note: the means tensor is expected to be precomputed by the user. It can also contain any valid values (not required to be actual means, and can be for instance a result of a convolution with a Gaussian kernel).
 dy

Input. Tensor pointer in device memory for the layer's dy cumulative loss differential data (error backpropagation).
 temp, temp2

Workspace. Temporary tensors in device memory. These are used for computing intermediate values during the backward pass. These tensors do not have to be preserved from forward to backward pass. Both use xDesc as a descriptor.
 dxDesc

Input. Tensor descriptor for dx and dMeans.
 dx, dMeans

Output. Tensor pointers (in device memory) for the layer's resulting cumulative gradients dx and dMeans (dLoss/dx and dLoss/dMeans). Both share the same descriptor.
Possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The computation was performed successfully.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the tensor pointers
x, dx, temp, tmep2, dy
is NULL.  Number of any of the input or output tensor dimensions is not within the [4,5] range.
 Either alpha or beta pointer is NULL.
 A mismatch in dimensions between xDesc and dxDesc.
 LRN descriptor parameters are outside of their valid ranges.
 Any of the tensor strides is negative.
 One of the tensor pointers

CUDNN_STATUS_UNSUPPORTED

The function does not support the provided configuration. See the following for some examples of nonsupported configurations:
 Any of the input and output tensor strides mismatch (for the same dimension).
4.51. cudnnDivisiveNormalizationForward
cudnnStatus_t cudnnDivisiveNormalizationForward(
cudnnHandle_t handle,
cudnnLRNDescriptor_t normDesc,
cudnnDivNormMode_t mode,
const void *alpha,
const cudnnTensorDescriptor_t xDesc,
const void *x,
const void *means,
void *temp,
void *temp2,
const void *beta,
const cudnnTensorDescriptor_t yDesc,
void *y)
This function performs the forward spatial DivisiveNormalization layer computation. It divides every value in a layer by the standard deviation of its spatial neighbors as described in "What is the Best MultiStage Architecture for Object Recognition", Jarrett 2009, Local Contrast Normalization Layer section. Note that Divisive Normalization only implements the x/max(c, sigma_x) portion of the computation, where sigma_x is the variance over the spatial neighborhood of x. The full LCN (Local Contrastive Normalization) computation can be implemented as a twostep process:
x_m = xmean(x);
y = x_m/max(c, sigma(x_m));
The "xmean(x)" which is often referred to as "subtractive normalization" portion of the computation can be implemented using cuDNN average pooling layer followed by a call to addTensor.
Supported tensor formats are NCHW for 4D and NCDHW for 5D with any nonoverlapping nonnegative strides. Only 4D and 5D tensors are supported.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor.
 normDesc

Input. Handle to a previously intialized LRN parameter descriptor. This descriptor is used for both LRN and DivisiveNormalization layers.
 divNormMode

Input. DivisiveNormalization layer mode of operation. Currently only CUDNN_DIVNORM_PRECOMPUTED_MEANS is implemented. Normalization is performed using the means input tensor that is expected to be precomputed by the user.
 alpha, beta

Input. Pointers to scaling factors (in host memory) used to blend the layer output value with prior value in the destination tensor as follows: dstValue = alpha[0]*resultValue + beta[0]*priorDstValue. Please refer to this section for additional details.
 xDesc, yDesc

Input. Tensor descriptor objects for the input and output tensors. Note that xDesc is shared between x, means, temp and temp2 tensors.
 x

Input. Input tensor data pointer in device memory.
 means

Input. Input means tensor data pointer in device memory. Note that this tensor can be NULL (in that case its values are assumed to be zero during the computation). This tensor also doesn't have to contain means, these can be any values, a frequently used variation is a result of convolution with a normalized positive kernel (such as Gaussian).
 temp, temp2

Workspace. Temporary tensors in device memory. These are used for computing intermediate values during the forward pass. These tensors do not have to be preserved as inputs from forward to the backward pass. Both use xDesc as their descriptor.
 y

Output. Pointer in device memory to a tensor for the result of the forward DivisiveNormalization computation.
Possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The computation was performed successfully.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the tensor pointers
x, y, temp, temp2
is NULL.  Number of input tensor or output tensor dimensions is outside of [4,5] range.
 A mismatch in dimensions between any two of the input or output tensors.
 For inplace computation when pointers x == y, a mismatch in strides between the input data and output data tensors.
 Alpha or beta pointer is NULL.
 LRN descriptor parameters are outside of their valid ranges.
 Any of the tensor strides are negative.
 One of the tensor pointers

CUDNN_STATUS_UNSUPPORTED

The function does not support the provided configuration. See the following for some examples of nonsupported configurations:
 Any of the input and output tensor strides mismatch (for the same dimension).
4.52. cudnnDropoutBackward
cudnnStatus_t cudnnDropoutBackward(
cudnnHandle_t handle,
const cudnnDropoutDescriptor_t dropoutDesc,
const cudnnTensorDescriptor_t dydesc,
const void *dy,
const cudnnTensorDescriptor_t dxdesc,
void *dx,
void *reserveSpace,
size_t reserveSpaceSizeInBytes)
This function performs backward dropout operation over dy
returning results in dx
. If during forward dropout operation value from x
was propagated to y
then during backward operation value from dy
will be propagated to dx
, otherwise, dx
value will be set to 0
.
Better performance is obtained for fully packed tensors
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 dropoutDesc

Input. Previously created dropout descriptor object.
 dyDesc

Input. Handle to a previously initialized tensor descriptor.
 dy

Input. Pointer to data of the tensor described by the
dyDesc
descriptor.  dxDesc

Input. Handle to a previously initialized tensor descriptor.
 dx

Output. Pointer to data of the tensor described by the
dxDesc
descriptor.  reserveSpace

Input. Pointer to userallocated GPU memory used by this function. It is expected that
reserveSpace
was populated during a call tocudnnDropoutForward
and has not been changed.  reserveSpaceSizeInBytes

Input. Specifies size in bytes of the provided memory for the reserve space
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The call was successful.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The number of elements of input tensor and output tensors differ.
 The
datatype
of the input tensor and output tensors differs.  The strides of the input tensor and output tensors differ and inplace operation is used (i.e.,
x
andy
pointers are equal).  The provided
reserveSpaceSizeInBytes
is less then the value returned bycudnnDropoutGetReserveSpaceSize
cudnnSetDropoutDescriptor
has not been called ondropoutDesc
with the nonNULLstates
argument

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.
4.53. cudnnDropoutForward
cudnnStatus_t cudnnDropoutForward(
cudnnHandle_t handle,
const cudnnDropoutDescriptor_t dropoutDesc,
const cudnnTensorDescriptor_t xdesc,
const void *x,
const cudnnTensorDescriptor_t ydesc,
void *y,
void *reserveSpace,
size_t reserveSpaceSizeInBytes)
This function performs forward dropout operation over x
returning results in y
. If dropout
was used as a parameter to cudnnSetDropoutDescriptor
, the approximately dropout
fraction of x
values will be replaces by 0
, and the rest will be scaled by 1/(1dropout)
This function should not be running concurrently with another cudnnDropoutForward
function using the same states
.
Better performance is obtained for fully packed tensors
Should not be called during inference
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 dropoutDesc

Input. Previously created dropout descriptor object.
 xDesc

Input. Handle to a previously initialized tensor descriptor.
 x

Input. Pointer to data of the tensor described by the
xDesc
descriptor.  yDesc

Input. Handle to a previously initialized tensor descriptor.
 y

Output. Pointer to data of the tensor described by the
yDesc
descriptor.  reserveSpace

Output. Pointer to userallocated GPU memory used by this function. It is expected that contents of
reserveSpace
doe not change betweencudnnDropoutForward
andcudnnDropoutBackward
calls.  reserveSpaceSizeInBytes

Input. Specifies size in bytes of the provided memory for the reserve space.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The call was successful.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The number of elements of input tensor and output tensors differ.
 The
datatype
of the input tensor and output tensors differs.  The strides of the input tensor and output tensors differ and inplace operation is used (i.e.,
x
andy
pointers are equal).  The provided
reserveSpaceSizeInBytes
is less then the value returned bycudnnDropoutGetReserveSpaceSize
. cudnnSetDropoutDescriptor
has not been called ondropoutDesc
with the nonNULLstates
argument.

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.
4.54. cudnnDropoutGetReserveSpaceSize
cudnnStatus_t cudnnDropoutGetReserveSpaceSize(
cudnnTensorDescriptor_t xDesc,
size_t *sizeInBytes)
This function is used to query the amount of reserve needed to run dropout with the input dimensions given by xDesc
. The same reserve space is expected to be passed to cudnnDropoutForward
and cudnnDropoutBackward
, and its contents is expected to remain unchanged between cudnnDropoutForward
and cudnnDropoutBackward
calls.
Parameters
 xDesc

Input. Handle to a previously initialized tensor descriptor, describing input to a dropout operation.
 sizeInBytes

Output. Amount of GPU memory needed as reserve space to be able to run dropout with an input tensor descriptor specified by xDesc.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.
4.55. cudnnDropoutGetStatesSize
cudnnStatus_t cudnnDropoutGetStatesSize(
cudnnHandle_t handle,
size_t *sizeInBytes)
This function is used to query the amount of space required to store the states of the random number generators used by cudnnDropoutForward
function.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 sizeInBytes

Output. Amount of GPU memory needed to store random generator states.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.
4.56. cudnnFindConvolutionBackwardDataAlgorithm
cudnnStatus_t cudnnFindConvolutionBackwardDataAlgorithm(
cudnnHandle_t handle,
const cudnnFilterDescriptor_t wDesc,
const cudnnTensorDescriptor_t dyDesc,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnTensorDescriptor_t dxDesc,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnConvolutionBwdDataAlgoPerf_t *perfResults)
This function attempts all cuDNN algorithms (including CUDNN_TENSOR_OP_MATH and CUDNN_DEFAULT_MATH versions of algorithms where CUDNN_TENSOR_OP_MATH may be available) for cudnnConvolutionBackwardData()
, using memory allocated via cudaMalloc()
and outputs performance metrics to a userallocated array of cudnnConvolutionBwdDataAlgoPerf_t
. These metrics are written in sorted fashion where the first element has the lowest compute time. The total number of resulting algorithms can be queried through the API cudnnGetConvolutionBackwardMaxCount()
.
This function is host blocking.
It is recommend to run this function prior to allocating layer data; doing otherwise may needlessly inhibit some algorithm options due to resource usage.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 wDesc

Input. Handle to a previously initialized filter descriptor.
 dyDesc

Input. Handle to the previously initialized input differential tensor descriptor.
 convDesc

Input. Previously initialized convolution descriptor.
 dxDesc

Input. Handle to the previously initialized output tensor descriptor.
 requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
handle
is not allocated properly.wDesc
,dyDesc
ordxDesc
is not allocated properly.wDesc
,dyDesc
ordxDesc
has fewer than 1 dimension. Either
returnedCount
orperfResults
is nil. requestedCount
is less than 1.

CUDNN_STATUS_ALLOC_FAILED

This function was unable to allocate memory to store sample input, filters and output.

CUDNN_STATUS_INTERNAL_ERROR

At least one of the following conditions are met:
 The function was unable to allocate neccesary timing objects.
 The function was unable to deallocate neccesary timing objects.
 The function was unable to deallocate sample input, filters and output.
4.57. cudnnFindConvolutionBackwardDataAlgorithmEx
cudnnStatus_t cudnnFindConvolutionBackwardDataAlgorithmEx(
cudnnHandle_t handle,
const cudnnFilterDescriptor_t wDesc,
const void *w,
const cudnnTensorDescriptor_t dyDesc,
const void *dy,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnTensorDescriptor_t dxDesc,
void *dx,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnConvolutionBwdDataAlgoPerf_t *perfResults,
void *workSpace,
size_t workSpaceSizeInBytes)
This function attempts all cuDNN algorithms (including CUDNN_TENSOR_OP_MATH and CUDNN_DEFAULT_MATH versions of algorithms where CUDNN_TENSOR_OP_MATH may be available) for cudnnConvolutionBackwardData
, using userallocated GPU memory, and outputs performance metrics to a userallocated array of cudnnConvolutionBwdDataAlgoPerf_t
. These metrics are written in sorted fashion where the first element has the lowest compute time. The total number of resulting algorithms can be queried through the API cudnnGetConvolutionBackwardMaxCount()
.
This function is host blocking.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 wDesc

Input. Handle to a previously initialized filter descriptor.
 w

Input. Data pointer to GPU memory associated with the filter descriptor
wDesc
.  dyDesc

Input. Handle to the previously initialized input differential tensor descriptor.
 dy

Input. Data pointer to GPU memory associated with the filter descriptor
dyDesc
.  convDesc

Input. Previously initialized convolution descriptor.
 dxDesc

Input. Handle to the previously initialized output tensor descriptor.
 dxDesc

Input/Output. Data pointer to GPU memory associated with the tensor descriptor
dxDesc
. The content of this tensor will be overwritten with arbitary values.  requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
 workSpace

Input. Data pointer to GPU memory that is a necessary workspace for some algorithms. The size of this workspace will determine the availabilty of algorithms. A nil pointer is considered a workSpace of 0 bytes.
 workSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
workSpace
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
handle
is not allocated properly.wDesc
,dyDesc
ordxDesc
is not allocated properly.wDesc
,dyDesc
ordxDesc
has fewer than 1 dimension.w
,dy
ordx
is nil. Either
returnedCount
orperfResults
is nil. requestedCount
is less than 1.

CUDNN_STATUS_INTERNAL_ERROR

At least one of the following conditions are met:
 The function was unable to allocate neccesary timing objects.
 The function was unable to deallocate neccesary timing objects.
 The function was unable to deallocate sample input, filters and output.
4.58. cudnnFindConvolutionBackwardFilterAlgorithm
cudnnStatus_t cudnnFindConvolutionBackwardFilterAlgorithm(
cudnnHandle_t handle,
const cudnnTensorDescriptor_t xDesc,
const cudnnTensorDescriptor_t dyDesc,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnFilterDescriptor_t dwDesc,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnConvolutionBwdFilterAlgoPerf_t *perfResults)
This function attempts all cuDNN algorithms (including CUDNN_TENSOR_OP_MATH and CUDNN_DEFAULT_MATH versions of algorithms where CUDNN_TENSOR_OP_MATH may be available) for cudnnConvolutionBackwardFilter()
, using GPU memory allocated via cudaMalloc()
, and outputs performance metrics to a userallocated array of cudnnConvolutionBwdFilterAlgoPerf_t
. These metrics are written in sorted fashion where the first element has the lowest compute time. The total number of resulting algorithms can be queried through the API cudnnGetConvolutionBackwardMaxCount()
.
This function is host blocking.
It is recommend to run this function prior to allocating layer data; doing otherwise may needlessly inhibit some algorithm options due to resource usage.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 xDesc

Input. Handle to the previously initialized input tensor descriptor.
 dyDesc

Input. Handle to the previously initialized input differential tensor descriptor.
 convDesc

Input. Previously initialized convolution descriptor.
 dwDesc

Input. Handle to a previously initialized filter descriptor.
 requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
handle
is not allocated properly.xDesc
,dyDesc
ordwDesc
is not allocated properly.xDesc
,dyDesc
ordwDesc
has fewer than 1 dimension. Either
returnedCount
orperfResults
is nil. requestedCount
is less than 1.

CUDNN_STATUS_ALLOC_FAILED

This function was unable to allocate memory to store sample input, filters and output.

CUDNN_STATUS_INTERNAL_ERROR

At least one of the following conditions are met:
 The function was unable to allocate neccesary timing objects.
 The function was unable to deallocate neccesary timing objects.
 The function was unable to deallocate sample input, filters and output.
4.59. cudnnFindConvolutionBackwardFilterAlgorithmEx
cudnnStatus_t cudnnFindConvolutionBackwardFilterAlgorithmEx(
cudnnHandle_t handle,
const cudnnTensorDescriptor_t xDesc,
const void *x,
const cudnnTensorDescriptor_t dyDesc,
const void *dy,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnFilterDescriptor_t dwDesc,
void *dw,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnConvolutionBwdFilterAlgoPerf_t *perfResults,
void *workSpace,
size_t workSpaceSizeInBytes)
This function attempts all cuDNN algorithms (including CUDNN_TENSOR_OP_MATH and CUDNN_DEFAULT_MATH versions of algorithms where CUDNN_TENSOR_OP_MATH may be available) for cudnnConvolutionBackwardFilter
, using userallocated GPU memory, and outputs performance metrics to a userallocated array of cudnnConvolutionBwdFilterAlgoPerf_t
. These metrics are written in sorted fashion where the first element has the lowest compute time. The total number of resulting algorithms can be queried through the API cudnnGetConvolutionBackwardMaxCount()
.
This function is host blocking.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 xDesc

Input. Handle to the previously initialized input tensor descriptor.
 x

Input. Data pointer to GPU memory associated with the filter descriptor
xDesc
.  dyDesc

Input. Handle to the previously initialized input differential tensor descriptor.
 dy

Input. Data pointer to GPU memory associated with the tensor descriptor
dyDesc
.  convDesc

Input. Previously initialized convolution descriptor.
 dwDesc

Input. Handle to a previously initialized filter descriptor.
 dw

Input/Output. Data pointer to GPU memory associated with the filter descriptor
dwDesc
. The content of this tensor will be overwritten with arbitary values.  requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
 workSpace

Input. Data pointer to GPU memory that is a necessary workspace for some algorithms. The size of this workspace will determine the availabilty of algorithms. A nil pointer is considered a workSpace of 0 bytes.
 workSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
workSpace
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
handle
is not allocated properly.xDesc
,dyDesc
ordwDesc
is not allocated properly.xDesc
,dyDesc
ordwDesc
has fewer than 1 dimension.x
,dy
ordw
is nil. Either
returnedCount
orperfResults
is nil. requestedCount
is less than 1.

CUDNN_STATUS_INTERNAL_ERROR

At least one of the following conditions are met:
 The function was unable to allocate neccesary timing objects.
 The function was unable to deallocate neccesary timing objects.
 The function was unable to deallocate sample input, filters and output.
4.60. cudnnFindConvolutionForwardAlgorithm
cudnnStatus_t cudnnFindConvolutionForwardAlgorithm(
cudnnHandle_t handle,
const cudnnTensorDescriptor_t xDesc,
const cudnnFilterDescriptor_t wDesc,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnTensorDescriptor_t yDesc,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnConvolutionFwdAlgoPerf_t *perfResults)
This function attempts all cuDNN algorithms (including CUDNN_TENSOR_OP_MATH and CUDNN_DEFAULT_MATH versions of algorithms where CUDNN_TENSOR_OP_MATH may be available) for cudnnConvolutionForward()
, using memory allocated via cudaMalloc()
, and outputs performance metrics to a userallocated array of cudnnConvolutionFwdAlgoPerf_t
. These metrics are written in sorted fashion where the first element has the lowest compute time. The total number of resulting algorithms can be queried through the API cudnnGetConvolutionForwardMaxCount()
.
This function is host blocking.
It is recommend to run this function prior to allocating layer data; doing otherwise may needlessly inhibit some algorithm options due to resource usage.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 xDesc

Input. Handle to the previously initialized input tensor descriptor.
 wDesc

Input. Handle to a previously initialized filter descriptor.
 convDesc

Input. Previously initialized convolution descriptor.
 yDesc

Input. Handle to the previously initialized output tensor descriptor.
 requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
handle
is not allocated properly.xDesc
,wDesc
oryDesc
is not allocated properly.xDesc
,wDesc
oryDesc
has fewer than 1 dimension. Either
returnedCount
orperfResults
is nil. requestedCount
is less than 1.

CUDNN_STATUS_ALLOC_FAILED

This function was unable to allocate memory to store sample input, filters and output.

CUDNN_STATUS_INTERNAL_ERROR

At least one of the following conditions are met:
 The function was unable to allocate neccesary timing objects.
 The function was unable to deallocate neccesary timing objects.
 The function was unable to deallocate sample input, filters and output.
4.61. cudnnFindConvolutionForwardAlgorithmEx
cudnnStatus_t cudnnFindConvolutionForwardAlgorithmEx(
cudnnHandle_t handle,
const cudnnTensorDescriptor_t xDesc,
const void *x,
const cudnnFilterDescriptor_t wDesc,
const void *w,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnTensorDescriptor_t yDesc,
void *y,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnConvolutionFwdAlgoPerf_t *perfResults,
void *workSpace,
size_t workSpaceSizeInBytes)
This function attempts all available cuDNN algorithms (including CUDNN_TENSOR_OP_MATH and CUDNN_DEFAULT_MATH versions of algorithms where CUDNN_TENSOR_OP_MATH may be available) for cudnnConvolutionForward
, using userallocated GPU memory, and outputs performance metrics to a userallocated array of cudnnConvolutionFwdAlgoPerf_t
. These metrics are written in sorted fashion where the first element has the lowest compute time. The total number of resulting algorithms can be queried through the API cudnnGetConvolutionForwardMaxCount()
.
This function is host blocking.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 xDesc

Input. Handle to the previously initialized input tensor descriptor.
 x

Input. Data pointer to GPU memory associated with the tensor descriptor
xDesc
.  wDesc

Input. Handle to a previously initialized filter descriptor.
 w

Input. Data pointer to GPU memory associated with the filter descriptor
wDesc
.  convDesc

Input. Previously initialized convolution descriptor.
 yDesc

Input. Handle to the previously initialized output tensor descriptor.
 y

Input/Output. Data pointer to GPU memory associated with the tensor descriptor
yDesc
. The content of this tensor will be overwritten with arbitary values.  requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
 workSpace

Input. Data pointer to GPU memory that is a necessary workspace for some algorithms. The size of this workspace will determine the availability of algorithms. A nil pointer is considered a workSpace of 0 bytes.
 workSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
workSpace
.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
handle
is not allocated properly.xDesc
,wDesc
oryDesc
is not allocated properly.xDesc
,wDesc
oryDesc
has fewer than 1 dimension.x
,w
ory
is nil. Either
returnedCount
orperfResults
is nil. requestedCount
is less than 1.

CUDNN_STATUS_INTERNAL_ERROR

At least one of the following conditions are met:
 The function was unable to allocate neccesary timing objects.
 The function was unable to deallocate neccesary timing objects.
 The function was unable to deallocate sample input, filters and output.
4.62. cudnnFindRNNBackwardDataAlgorithmEx
cudnnStatus_t cudnnFindRNNBackwardDataAlgorithmEx(
cudnnHandle_t handle,
const cudnnRNNDescriptor_t rnnDesc,
const int seqLength,
const cudnnTensorDescriptor_t *yDesc,
const void *y,
const cudnnTensorDescriptor_t *dyDesc,
const void *dy,
const cudnnTensorDescriptor_t dhyDesc,
const void *dhy,
const cudnnTensorDescriptor_t dcyDesc,
const void *dcy,
const cudnnFilterDescriptor_t wDesc,
const void *w,
const cudnnTensorDescriptor_t hxDesc,
const void *hx,
const cudnnTensorDescriptor_t cxDesc,
const void *cx,
const cudnnTensorDescriptor_t *dxDesc,
void *dx,
const cudnnTensorDescriptor_t dhxDesc,
void *dhx,
const cudnnTensorDescriptor_t dcxDesc,
void *dcx,
const float findIntensity,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnAlgorithmPerformance_t *perfResults,
void *workspace,
size_t workSpaceSizeInBytes,
const void *reserveSpace,
size_t reserveSpaceSizeInBytes)
(New for 7.1)
This function attempts all available cuDNN algorithms for cudnnRNNBackwardData
, using userallocated GPU memory. It outputs the parameters that influence the performance of the algorithm to a userallocated array of cudnnAlgorithmPerformance_t
. These parameter metrics are written in sorted fashion where the first element has the lowest compute time.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 rnnDesc

Input. A previously initialized RNN descriptor.
 seqLength

Input. Number of iterations to unroll over. The value of this
seqLength
must not exceed the value that was used incudnnGetRNNWorkspaceSize()
function for querying the workspace size required to execute the RNN.  yDesc

Input. An array of fully packed tensor descriptors describing the output from each recurrent iteration (one descriptor per iteration). The second dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the second dimension should match thehiddenSize
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the second dimension should match double thehiddenSize
argument passed tocudnnSetRNNDescriptor
.
The first dimension of the tensor
n
must match the first dimension of the tensorn
indyDesc
.
 If
 y

Input. Data pointer to GPU memory associated with the output tensor descriptor
yDesc
.  dyDesc

Input. An array of fully packed tensor descriptors describing the gradient at the output from each recurrent iteration (one descriptor per iteration). The second dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the second dimension should match thehiddenSize
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the second dimension should match double thehiddenSize
argument passed tocudnnSetRNNDescriptor
.
The first dimension of the tensor
n
must match the second dimension of the tensorn
indxDesc
.
 If
 dy

Input. Data pointer to GPU memory associated with the tensor descriptors in the array
dyDesc
.  dhyDesc

Input. A fully packed tensor descriptor describing the gradients at the final hidden state of the RNN. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
dxDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 dhy

Input. Data pointer to GPU memory associated with the tensor descriptor
dhyDesc
. If a NULL pointer is passed, the gradients at the final hidden state of the network will be initialized to zero.  dcyDesc

Input. A fully packed tensor descriptor describing the gradients at the final cell state of the RNN. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
dxDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 dcy

Input. Data pointer to GPU memory associated with the tensor descriptor
dcyDesc
. If a NULL pointer is passed, the gradients at the final cell state of the network will be initialized to zero.  wDesc

Input. Handle to a previously initialized filter descriptor describing the weights for the RNN.
 w

Input. Data pointer to GPU memory associated with the filter descriptor
wDesc
.  hxDesc

Input. A fully packed tensor descriptor describing the initial hidden state of the RNN. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
dxDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 hx

Input. Data pointer to GPU memory associated with the tensor descriptor
hxDesc
. If a NULL pointer is passed, the initial hidden state of the network will be initialized to zero.  cxDesc

Input. A fully packed tensor descriptor describing the initial cell state for LSTM networks. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
dxDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 cx

Input. Data pointer to GPU memory associated with the tensor descriptor
cxDesc
. If a NULL pointer is passed, the initial cell state of the network will be initialized to zero.  dxDesc

Input. An array of fully packed tensor descriptors describing the gradient at the input of each recurrent iteration (one descriptor per iteration). The first dimension (batch size) of the tensors may decrease from element
n
to elementn+1
but may not increase. Each tensor descriptor must have the same second dimension (vector length).  dx

Output. Data pointer to GPU memory associated with the tensor descriptors in the array
dxDesc
.  dhxDesc

Input. A fully packed tensor descriptor describing the gradient at the initial hidden state of the RNN. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
dxDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 dhx

Output. Data pointer to GPU memory associated with the tensor descriptor
dhxDesc
. If a NULL pointer is passed, the gradient at the hidden input of the network will not be set.  dcxDesc

Input. A fully packed tensor descriptor describing the gradient at the initial cell state of the RNN. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
dxDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 dcx

Output. Data pointer to GPU memory associated with the tensor descriptor
dcxDesc
. If a NULL pointer is passed, the gradient at the cell input of the network will not be set.  findIntensity

Input.This input was previously unused in versions prior to 7.2.0. It is used in cuDNN 7.2.0 and later versions to control the overall runtime of the RNN find algorithms, by selecting the percentage of a large Cartesian product space to be searched.
 Setting
findIntensity
within the range (0,1.] will set a percentage of the entire RNN search space to search. WhenfindIntensity
is set to 1.0, a full search is performed over all RNN parameters.  When
findIntensity
is set to 0.0f, a quick, minimal search is performed. This setting has the best runtime. However, in this case the parameters returned by this function will not correspond to the best performance of the algorithm; a longer search might discover better parameters. This option will execute up to three instances of the configured RNN problem. Runtime will vary proportionally to RNN problem size, as it will in the other cases, hence no guarantee of an explicit time bound can be given.  Setting
findIntensity
within the range [1.,0) sets a percentage of a reduced Cartesian product space to be searched. This reduced searched space has been heuristically selected to have good performance. The setting of 1.0 represents a full search over this reduced search space.  Values outside the range [1,1] are truncated to the range [1,1], and then interpreted as per the above.
 Setting
findIntensity
to 1.0 in cuDNN 7.2 and later versions is equivalent to the behavior of this function in versions prior to cuDNN 7.2.0.  This function times the single RNN executions over large parameter spacesone execution per parameter combination. The times returned by this function are latencies.
 Setting
 requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
 workspace

Input. Data pointer to GPU memory to be used as a workspace for this call.
 workSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
workspace
.  reserveSpace

Input/Output. Data pointer to GPU memory to be used as a reserve space for this call.
 reserveSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
reserveSpace
.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The function launched successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The descriptor
rnnDesc
is invalid.  At least one of the descriptors
dhxDesc, wDesc, hxDesc, cxDesc, dcxDesc, dhyDesc, dcyDesc
or one of the descriptors inyDesc, dxdesc, dydesc
is invalid.  The descriptors in one of
yDesc, dxDesc, dyDesc, dhxDesc, wDesc, hxDesc, cxDesc, dcxDesc, dhyDesc, dcyDesc
has incorrect strides or dimensions. workSpaceSizeInBytes
is too small.reserveSpaceSizeInBytes
is too small.
 The descriptor

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.

CUDNN_STATUS_ALLOC_FAILED

The function was unable to allocate memory.
4.63. cudnnFindRNNBackwardWeightsAlgorithmEx
cudnnStatus_t cudnnFindRNNBackwardWeightsAlgorithmEx(
cudnnHandle_t handle,
const cudnnRNNDescriptor_t rnnDesc,
const int seqLength,
const cudnnTensorDescriptor_t *xDesc,
const void *x,
const cudnnTensorDescriptor_t hxDesc,
const void *hx,
const cudnnTensorDescriptor_t *yDesc,
const void *y,
const float findIntensity,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnAlgorithmPerformance_t *perfResults,
const void *workspace,
size_t workSpaceSizeInBytes,
const cudnnFilterDescriptor_t dwDesc,
void *dw,
const void *reserveSpace,
size_t reserveSpaceSizeInBytes)
(New for 7.1)
This function attempts all available cuDNN algorithms for cudnnRNNBackwardWeights
, using userallocated GPU memory. It outputs the parameters that influence the performance of the algorithm to a userallocated array of cudnnAlgorithmPerformance_t
. These parameter metrics are written in sorted fashion where the first element has the lowest compute time.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 rnnDesc

Input. A previously initialized RNN descriptor.
 seqLength

Input. Number of iterations to unroll over. The value of this
seqLength
must not exceed the value that was used incudnnGetRNNWorkspaceSize()
function for querying the workspace size required to execute the RNN.  xDesc

Input. An array of fully packed tensor descriptors describing the input to each recurrent iteration (one descriptor per iteration). The first dimension (batch size) of the tensors may decrease from element
n
to elementn+1
but may not increase. Each tensor descriptor must have the same second dimension (vector length).  x

Input. Data pointer to GPU memory associated with the tensor descriptors in the array
xDesc
.  hxDesc

Input. A fully packed tensor descriptor describing the initial hidden state of the RNN. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
xDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 hx

Input. Data pointer to GPU memory associated with the tensor descriptor
hxDesc
. If a NULL pointer is passed, the initial hidden state of the network will be initialized to zero.  yDesc

Input. An array of fully packed tensor descriptors describing the output from each recurrent iteration (one descriptor per iteration). The second dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the second dimension should match thehiddenSize
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the second dimension should match double thehiddenSize
argument passed tocudnnSetRNNDescriptor
.
The first dimension of the tensor
n
must match the first dimension of the tensorn
indyDesc
.
 If
 y

Input. Data pointer to GPU memory associated with the output tensor descriptor
yDesc
.  findIntensity

Input.This input was previously unused in versions prior to 7.2.0. It is used in cuDNN 7.2.0 and later versions to control the overall runtime of the RNN find algorithms, by selecting the percentage of a large Cartesian product space to be searched.
 Setting
findIntensity
within the range (0,1.] will set a percentage of the entire RNN search space to search. WhenfindIntensity
is set to 1.0, a full search is performed over all RNN parameters.  When
findIntensity
is set to 0.0f, a quick, minimal search is performed. This setting has the best runtime. However, in this case the parameters returned by this function will not correspond to the best performance of the algorithm; a longer search might discover better parameters. This option will execute up to three instances of the configured RNN problem. Runtime will vary proportionally to RNN problem size, as it will in the other cases, hence no guarantee of an explicit time bound can be given.  Setting
findIntensity
within the range [1.,0) sets a percentage of a reduced Cartesian product space to be searched. This reduced searched space has been heuristically selected to have good performance. The setting of 1.0 represents a full search over this reduced search space.  Values outside the range [1,1] are truncated to the range [1,1], and then interpreted as per the above.
 Setting
findIntensity
to 1.0 in cuDNN 7.2 and later versions is equivalent to the behavior of this function in versions prior to cuDNN 7.2.0.  This function times the single RNN executions over large parameter spacesone execution per parameter combination. The times returned by this function are latencies.
 Setting
 requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
 workspace

Input. Data pointer to GPU memory to be used as a workspace for this call.
 workSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
workspace
.  dwDesc

Input. Handle to a previously initialized filter descriptor describing the gradients of the weights for the RNN.
 dw

Input/Output. Data pointer to GPU memory associated with the filter descriptor
dwDesc
.  reserveSpace

Input. Data pointer to GPU memory to be used as a reserve space for this call.
 reserveSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
reserveSpace
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The function launched successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The descriptor
rnnDesc
is invalid.  At least one of the descriptors
hxDesc, dwDesc
or one of the descriptors inxDesc, yDesc
is invalid.  The descriptors in one of
xDesc, hxDesc, yDesc, dwDesc
has incorrect strides or dimensions. workSpaceSizeInBytes
is too small.reserveSpaceSizeInBytes
is too small.
 The descriptor

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.

CUDNN_STATUS_ALLOC_FAILED

The function was unable to allocate memory.
4.64. cudnnFindRNNForwardInferenceAlgorithmEx
cudnnStatus_t cudnnFindRNNForwardInferenceAlgorithmEx(
cudnnHandle_t handle,
const cudnnRNNDescriptor_t rnnDesc,
const int seqLength,
const cudnnTensorDescriptor_t *xDesc,
const void *x,
const cudnnTensorDescriptor_t hxDesc,
const void *hx,
const cudnnTensorDescriptor_t cxDesc,
const void *cx,
const cudnnFilterDescriptor_t wDesc,
const void *w,
const cudnnTensorDescriptor_t *yDesc,
void *y,
const cudnnTensorDescriptor_t hyDesc,
void *hy,
const cudnnTensorDescriptor_t cyDesc,
void *cy,
const float findIntensity,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnAlgorithmPerformance_t *perfResults,
void *workspace,
size_t workSpaceSizeInBytes)
(New for 7.1)
This function attempts all available cuDNN algorithms for cudnnRNNForwardInference
, using userallocated GPU memory. It outputs the parameters that influence the performance of the algorithm to a userallocated array of cudnnAlgorithmPerformance_t
. These parameter metrics are written in sorted fashion where the first element has the lowest compute time.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 rnnDesc

Input. A previously initialized RNN descriptor.
 seqLength

Input. Number of iterations to unroll over. The value of this
seqLength
must not exceed the value that was used incudnnGetRNNWorkspaceSize()
function for querying the workspace size required to execute the RNN.  xDesc

Input. An array of fully packed tensor descriptors describing the input to each recurrent iteration (one descriptor per iteration). The first dimension (batch size) of the tensors may decrease from element
n
to elementn+1
but may not increase. Each tensor descriptor must have the same second dimension (vector length).  x

Input. Data pointer to GPU memory associated with the tensor descriptors in the array
xDesc
. The data are expected to be packed contiguously with the first element of iteration n+1 following directly from the last element of iteration n.  hxDesc

Input. A fully packed tensor descriptor describing the initial hidden state of the RNN. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
xDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 hx

Input. Data pointer to GPU memory associated with the tensor descriptor
hxDesc
. If a NULL pointer is passed, the initial hidden state of the network will be initialized to zero.  cxDesc

Input. A fully packed tensor descriptor describing the initial cell state for LSTM networks. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
xDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 cx

Input. Data pointer to GPU memory associated with the tensor descriptor
cxDesc
. If a NULL pointer is passed, the initial cell state of the network will be initialized to zero.  wDesc

Input. Handle to a previously initialized filter descriptor describing the weights for the RNN.
 w

Input. Data pointer to GPU memory associated with the filter descriptor
wDesc
.  yDesc

Input. An array of fully packed tensor descriptors describing the output from each recurrent iteration (one descriptor per iteration). The second dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the second dimension should match thehiddenSize
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the second dimension should match double thehiddenSize
argument passed tocudnnSetRNNDescriptor
.
The first dimension of the tensor
n
must match the first dimension of the tensorn
inxDesc
.
 If
 y

Output. Data pointer to GPU memory associated with the output tensor descriptor
yDesc
. The data are expected to be packed contiguously with the first element of iteration n+1 following directly from the last element of iteration n.  hyDesc

Input. A fully packed tensor descriptor describing the final hidden state of the RNN. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
xDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 hy

Output. Data pointer to GPU memory associated with the tensor descriptor
hyDesc
. If a NULL pointer is passed, the final hidden state of the network will not be saved.  cyDesc

Input. A fully packed tensor descriptor describing the final cell state for LSTM networks. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
xDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 cy

Output. Data pointer to GPU memory associated with the tensor descriptor
cyDesc
. If a NULL pointer is passed, the final cell state of the network will be not be saved.  findIntensity

Input.This input was previously unused in versions prior to 7.2.0. It is used in cuDNN 7.2.0 and later versions to control the overall runtime of the RNN find algorithms, by selecting the percentage of a large Cartesian product space to be searched.
 Setting
findIntensity
within the range (0,1.] will set a percentage of the entire RNN search space to search. WhenfindIntensity
is set to 1.0, a full search is performed over all RNN parameters.  When
findIntensity
is set to 0.0f, a quick, minimal search is performed. This setting has the best runtime. However, in this case the parameters returned by this function will not correspond to the best performance of the algorithm; a longer search might discover better parameters. This option will execute up to three instances of the configured RNN problem. Runtime will vary proportionally to RNN problem size, as it will in the other cases, hence no guarantee of an explicit time bound can be given.  Setting
findIntensity
within the range [1.,0) sets a percentage of a reduced Cartesian product space to be searched. This reduced searched space has been heuristically selected to have good performance. The setting of 1.0 represents a full search over this reduced search space.  Values outside the range [1,1] are truncated to the range [1,1], and then interpreted as per the above.
 Setting
findIntensity
to 1.0 in cuDNN 7.2 and later versions is equivalent to the behavior of this function in versions prior to cuDNN 7.2.0.  This function times the single RNN executions over large parameter spacesone execution per parameter combination. The times returned by this function are latencies.
 Setting
 requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
 workspace

Input. Data pointer to GPU memory to be used as a workspace for this call.
 workSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
workspace
.
Returns

CUDNN_STATUS_SUCCESS

The function launched successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The descriptor
rnnDesc
is invalid.  At least one of the descriptors
hxDesc, cxDesc, wDesc, hyDesc, cyDesc
or one of the descriptors inxDesc, yDesc
is invalid.  The descriptors in one of
xDesc, hxDesc, cxDesc, wDesc, yDesc, hyDesc, cyDesc
have incorrect strides or dimensions. workSpaceSizeInBytes
is too small.
 The descriptor

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.

CUDNN_STATUS_ALLOC_FAILED

The function was unable to allocate memory.
4.65. cudnnFindRNNForwardTrainingAlgorithmEx
cudnnStatus_t cudnnFindRNNForwardTrainingAlgorithmEx(
cudnnHandle_t handle,
const cudnnRNNDescriptor_t rnnDesc,
const int seqLength,
const cudnnTensorDescriptor_t *xDesc,
const void *x,
const cudnnTensorDescriptor_t hxDesc,
const void *hx,
const cudnnTensorDescriptor_t cxDesc,
const void *cx,
const cudnnFilterDescriptor_t wDesc,
const void *w,
const cudnnTensorDescriptor_t *yDesc,
void *y,
const cudnnTensorDescriptor_t hyDesc,
void *hy,
const cudnnTensorDescriptor_t cyDesc,
void *cy,
const float findIntensity,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnAlgorithmPerformance_t *perfResults,
void *workspace,
size_t workSpaceSizeInBytes,
void *reserveSpace,
size_t reserveSpaceSizeInBytes)
(New for 7.1)
This function attempts all available cuDNN algorithms for cudnnRNNForwardTraining
, using userallocated GPU memory. It outputs the parameters that influence the performance of the algorithm to a userallocated array of cudnnAlgorithmPerformance_t
. These parameter metrics are written in sorted fashion where the first element has the lowest compute time.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 rnnDesc

Input. A previously initialized RNN descriptor.
 xDesc

Input. An array of fully packed tensor descriptors describing the input to each recurrent iteration (one descriptor per iteration). The first dimension (batch size) of the tensors may decrease from element
n
to elementn+1
but may not increase. Each tensor descriptor must have the same second dimension (vector length).  seqLength

Input. Number of iterations to unroll over. The value of this
seqLength
must not exceed the value that was used incudnnGetRNNWorkspaceSize()
function for querying the workspace size required to execute the RNN.  x

Input. Data pointer to GPU memory associated with the tensor descriptors in the array
xDesc
.  hxDesc

Input. A fully packed tensor descriptor describing the initial hidden state of the RNN. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
xDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 hx

Input. Data pointer to GPU memory associated with the tensor descriptor
hxDesc
. If a NULL pointer is passed, the initial hidden state of the network will be initialized to zero.  cxDesc

Input. A fully packed tensor descriptor describing the initial cell state for LSTM networks. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
xDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 cx

Input. Data pointer to GPU memory associated with the tensor descriptor
cxDesc
. If a NULL pointer is passed, the initial cell state of the network will be initialized to zero.  wDesc

Input. Handle to a previously initialized filter descriptor describing the weights for the RNN.
 w

Input. Data pointer to GPU memory associated with the filter descriptor
wDesc
.  yDesc

Input. An array of fully packed tensor descriptors describing the output from each recurrent iteration (one descriptor per iteration). The second dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the second dimension should match thehiddenSize
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the second dimension should match double thehiddenSize
argument passed tocudnnSetRNNDescriptor
.
The first dimension of the tensor
n
must match the first dimension of the tensorn
inxDesc
.
 If
 y

Output. Data pointer to GPU memory associated with the output tensor descriptor
yDesc
.  hyDesc

Input. A fully packed tensor descriptor describing the final hidden state of the RNN. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
xDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 hy

Output. Data pointer to GPU memory associated with the tensor descriptor
hyDesc
. If a NULL pointer is passed, the final hidden state of the network will not be saved.  cyDesc

Input. A fully packed tensor descriptor describing the final cell state for LSTM networks. The first dimension of the tensor depends on the
direction
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
: If
direction
isCUDNN_UNIDIRECTIONAL
the first dimension should match thenumLayers
argument passed tocudnnSetRNNDescriptor
.  If
direction
isCUDNN_BIDIRECTIONAL
the first dimension should match double thenumLayers
argument passed tocudnnSetRNNDescriptor
.
The second dimension must match the first dimension of the tensors described in
xDesc
. The third dimension must match thehiddenSize
argument passed to thecudnnSetRNNDescriptor
call used to initializernnDesc
. The tensor must be fully packed.
 If
 cy

Output. Data pointer to GPU memory associated with the tensor descriptor
cyDesc
. If a NULL pointer is passed, the final cell state of the network will be not be saved.  findIntensity

Input.This input was previously unused in versions prior to 7.2.0. It is used in cuDNN 7.2.0 and later versions to control the overall runtime of the RNN find algorithms, by selecting the percentage of a large Cartesian product space to be searched.
 Setting
findIntensity
within the range (0,1.] will set a percentage of the entire RNN search space to search. WhenfindIntensity
is set to 1.0, a full search is performed over all RNN parameters.  When
findIntensity
is set to 0.0f, a quick, minimal search is performed. This setting has the best runtime. However, in this case the parameters returned by this function will not correspond to the best performance of the algorithm; a longer search might discover better parameters. This option will execute up to three instances of the configured RNN problem. Runtime will vary proportionally to RNN problem size, as it will in the other cases, hence no guarantee of an explicit time bound can be given.  Setting
findIntensity
within the range [1.,0) sets a percentage of a reduced Cartesian product space to be searched. This reduced searched space has been heuristically selected to have good performance. The setting of 1.0 represents a full search over this reduced search space.  Values outside the range [1,1] are truncated to the range [1,1], and then interpreted as per the above.
 Setting
findIntensity
to 1.0 in cuDNN 7.2 and later versions is equivalent to the behavior of this function in versions prior to cuDNN 7.2.0.  This function times the single RNN executions over large parameter spacesone execution per parameter combination. The times returned by this function are latencies.
 Setting
 requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
 workspace

Input. Data pointer to GPU memory to be used as a workspace for this call.
 workSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
workspace
.  reserveSpace

Input/Output. Data pointer to GPU memory to be used as a reserve space for this call.
 reserveSpaceSizeInBytes

Input. Specifies the size in bytes of the provided
reserveSpace
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The function launched successfully.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The descriptor
rnnDesc
is invalid.  At least one of the descriptors
hxDesc, cxDesc, wDesc, hyDesc, cyDesc
or one of the descriptors inxDesc, yDesc
is invalid.  The descriptors in one of
xDesc, hxDesc, cxDesc, wDesc, yDesc, hyDesc, cyDesc
have incorrect strides or dimensions. workSpaceSizeInBytes
is too small.reserveSpaceSizeInBytes
is too small.
 The descriptor

CUDNN_STATUS_EXECUTION_FAILED

The function failed to launch on the GPU.

CUDNN_STATUS_ALLOC_FAILED

The function was unable to allocate memory.
4.66. cudnnGetActivationDescriptor
cudnnStatus_t cudnnGetActivationDescriptor(
const cudnnActivationDescriptor_t activationDesc,
cudnnActivationMode_t *mode,
cudnnNanPropagation_t *reluNanOpt,
double *coef)
This function queries a previously initialized generic activation descriptor object.
Parameters
 activationDesc

Input. Handle to a previously created activation descriptor.
 mode

Output. Enumerant to specify the activation mode.
 reluNanOpt

Output. Enumerant to specify the
Nan
propagation mode.  coef

Output. Floating point number to specify the clipping threashod when the activation mode is set to
CUDNN_ACTIVATION_CLIPPED_RELU
or to specify the alpha coefficient when the activation mode is set toCUDNN_ACTIVATION_ELU
.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The object was queried successfully.
4.67. cudnnGetAlgorithmDescriptor
cudnnStatus_t cudnnGetAlgorithmDescriptor(
const cudnnAlgorithmDescriptor_t algoDesc,
cudnnAlgorithm_t *algorithm)
(New for 7.1)
This function queries a previously initialized generic algorithm descriptor object.
Parameters
 algorithmDesc

Input. Handle to a previously created algorithm descriptor.
 algorithm

Input. Struct to specify the algorithm.
Returns

CUDNN_STATUS_SUCCESS

The object was queried successfully.
4.68. cudnnGetAlgorithmPerformance
cudnnStatus_t cudnnGetAlgorithmPerformance(
const cudnnAlgorithmPerformance_t algoPerf,
cudnnAlgorithmDescriptor_t* algoDesc,
cudnnStatus_t* status,
float* time,
size_t* memory)
(New for 7.1)
This function queries a previously initialized generic algorithm performance object.
Parameters
 algoPerf

Input/Output. Handle to a previously created algorithm performance object.
 algoDesc

Output. The algorithm descriptor which the performance results describe.
 status

Output. The cudnn status returned from running the algoDesc algorithm.
 timecoef

Output. The GPU time spent running the algoDesc algorithm.
 memory

Output. The GPU memory needed to run the algoDesc algorithm.
Returns

CUDNN_STATUS_SUCCESS

The object was queried successfully.
4.69. cudnnGetAlgorithmSpaceSize
cudnnStatus_t cudnnGetAlgorithmSpaceSize(
cudnnHandle_t handle,
cudnnAlgorithmDescriptor_t algoDesc,
size_t* algoSpaceSizeInBytes)
(New for 7.1)
This function queries for the amount of host memory needed to call cudnnSaveAlgorithm
, much like the “get workspace size” functions query for the amount of device memory needed.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 algoDesc

Input. A previously created algorithm descriptor.
 algoSpaceSizeInBytes

Ouptut. Amount of host memory needed as workspace to be able to save the metadata from the specified
algoDesc
.
Returns

CUDNN_STATUS_SUCCESS

The function launched successfully.

CUDNN_STATUS_BAD_PARAM

At least one of the arguments is null.
cudnnBatchNormalizationBackwardExWorkspaceSize
cudnnStatus_t cudnnGetBatchNormalizationBackwardExWorkspaceSize(
cudnnHandle_t handle,
cudnnBatchNormMode_t mode,
cudnnBatchNormOps_t bnOps,
const cudnnTensorDescriptor_t xDesc,
const cudnnTensorDescriptor_t yDesc,
const cudnnTensorDescriptor_t dyDesc,
const cudnnTensorDescriptor_t dzDesc,
const cudnnTensorDescriptor_t dxDesc,
const cudnnTensorDescriptor_t dBnScaleBiasDesc,
const cudnnActivationDescriptor_t activationDesc,
size_t *sizeInBytes);
This function returns the amount of GPU memory workspace the user should allocate to be able to call cudnnGetBatchNormalizationBackwardEx() function for the specified bnOps
input setting. The workspace allocated will then be passed to the function cudnnGetBatchNormalizationBackwardEx()
.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor. See cudnnHandle_t.
 mode

Input. Mode of operation (spatial or peractivation). See cudnnBatchNormMode_t.
 bnOps

Input. Mode of operation for the fast NHWC kernel. See cudnnBatchNormOps_t. This input can be used to set this function to perform either only the batch normalization, or batch normalization followed by activation, or batch normalization followed by elementwise addition and then activation.
 xDesc, yDesc, dyDesc, dzDesc, dxDesc

Tensor descriptors and pointers in the device memory for the layer's
x
data, back propagated differentialdy
(inputs), the optionaly
input data, the optionaldz
output, and thedx
output, which is the resulting differential with respect tox
. See cudnnTensorDescriptor_t.  dBnScaleBiasDesc

Input. Shared tensor descriptor for the following six tensors:
bnScaleData, bnBiasData, dBnScaleData, dBnBiasData, savedMean, and savedInvVariance.
This is the shared tensor descriptor desc for the secondary tensor that was derived by cudnnDeriveBNTensorDescriptor(). The dimensions for this tensor descriptor are dependent on normalization mode. Note: The data type of this tensor descriptor must be 'float' for FP16 and FP32 input tensors, and 'double' for FP64 input tensors.  activationDesc
 Input. Tensor descriptor for the activation operation.
 *sizeInBytes

Output. Amount of GPU memory required for the workspace, as determined by this function, to be able to execute the
cudnnGetBatchNormalizationBackwardEx()
function with the specifiedbnOps
input setting.
Possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The computation was performed successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 Number of
xDesc
oryDesc
ordxDesc
tensor descriptor dimensions is not within the range of [4,5] (only 4D and 5D tensors are supported.) dBnScaleBiasDesc
dimensions not 1xCx1x1 for 4D and 1xCx1x1x1 for 5D for spatial, and are not 1xCxHxW for 4D and 1xCxDxHxW for 5D for peractivation mode. Dimensions or data types mismatch for any pair of xDesc, dyDesc, dxDesc
 Number of
cudnnBatchNormalizationForwardTrainingExWorkspaceSize
cudnnStatus_t cudnnGetBatchNormalizationForwardTrainingExWorkspaceSize(
cudnnHandle_t handle,
cudnnBatchNormMode_t mode,
cudnnBatchNormOps_t bnOps,
const cudnnTensorDescriptor_t xDesc,
const cudnnTensorDescriptor_t zDesc,
const cudnnTensorDescriptor_t yDesc,
const cudnnTensorDescriptor_t bnScaleBiasMeanVarDesc,
const cudnnActivationDescriptor_t activationDesc,
size_t *sizeInBytes);
This function returns the amount of GPU memory workspace the user should allocate to be able to call cudnnGetBatchNormalizationForwardTrainingEx()
function for the specified bnOps
input setting. The workspace allocated should then be passed by the user to the function cudnnGetBatchNormalizationForwardTrainingEx()
.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor. See cudnnHandle_t.
 mode

Input. Mode of operation (spatial or peractivation). See cudnnBatchNormMode_t.
 bnOps
 Input. Mode of operation for the fast NHWC kernel. See cudnnBatchNormOps_t.. This input can be used to set this function to perform either only the batch normalization, or batch normalization followed by activation, or batch normalization followed by elementwise addition and then activation.
 xDesc, zDesc, yDesc

Tensor descriptors and pointers in the device memory for the layer's
x
data, the optionalz
input data, and they
output. See cudnnTensorDescriptor_t.  bnScaleBiasMeanVarDesc

Input. Shared tensor descriptor for the following six tensors:
bnScaleData, bnBiasData, dBnScaleData, dBnBiasData, savedMean, and savedInvVariance
. This is the shared tensor descriptor desc for the secondary tensor that was derived by cudnnDeriveBNTensorDescriptor(). The dimensions for this tensor descriptor are dependent on normalization mode. Note: The data type of this tensor descriptor must be 'float' for FP16 and FP32 input tensors, and 'double' for FP64 input tensors.  activationDesc

Input. Tensor descriptor for the activation operation. When the
bnOps
input is set to either CUDNN_BATCHNORM_OPS_BN_ACTIVATION or CUDNN_BATCHNORM_OPS_BN_ADD_ACTIVATION then this activation is used.
 *sizeInBytes

Output. Amount of GPU memory required for the workspace, as determined by this function, to be able to execute the
cudnnGetBatchNormalizationForwardTrainingEx()
function with the specifiedbnOps
input setting.
Returns

CUDNN_STATUS_SUCCESS

The computation was performed successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 Number of
xDesc
oryDesc
ordxDesc
tensor descriptor dimensions is not within the range of [4,5] (only 4D and 5D tensors are supported.) dBnScaleBiasDesc
dimensions not 1xCx1x1 for 4D and 1xCx1x1x1 for 5D for spatial, and are not 1xCxHxW for 4D and 1xCxDxHxW for 5D for peractivation mode. Dimensions or data types mismatch for
xDesc, yDesc
.
 Number of
4.72. cudnnGetBatchNormalizationTrainingExReserveSpaceSize
cudnnStatus_t cudnnGetBatchNormalizationTrainingExReserveSpaceSize(
cudnnHandle_t handle,
cudnnBatchNormMode_t mode,
cudnnBatchNormOps_t bnOps,
const cudnnActivationDescriptor_t activationDesc,
const cudnnTensorDescriptor_t xDesc,
size_t *sizeInBytes);
This function returns the amount of reserve GPU memory workspace the user should allocate for the batch normalization operation, for the specified bnOps
input setting. In contrast to the workspace
, the reserved space should be preserved between the forward and backward calls, and the data should not be altered.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor. See cudnnHandle_t.
 mode

Input. Mode of operation (spatial or peractivation). See cudnnBatchNormMode_t.
 bnOps
 Input. Mode of operation for the fast NHWC kernel. See cudnnBatchNormOps_t.. This input can be used to set this function to perform either only the batch normalization, or batch normalization followed by activation, or batch normalization followed by elementwise addition and then activation.
 xDesc

Tensor descriptors for the layer's x data. See cudnnTensorDescriptor_t.
 activationDesc
 Input. Tensor descriptor for the activation operation.
 *sizeInBytes
 Output. Amount of GPU memory reserved.
Possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The computation was performed successfully.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The
xDesc
tensor descriptor dimension is not within the [4,5] range (only 4D and 5D tensors are supported.)
 The
4.73. cudnnGetCTCLossDescriptor
cudnnStatus_t cudnnGetCTCLossDescriptor(
cudnnCTCLossDescriptor_t ctcLossDesc,
cudnnDataType_t* compType)
This function returns configuration of the passed CTC loss function descriptor.
Parameters
 ctcLossDesc

Input. CTC loss function descriptor passed, from which to retrieve the configuration.
 compType

Output. Compute type associated with this CTC loss function descriptor.
Returns

CUDNN_STATUS_SUCCESS

The function returned successfully.

CUDNN_STATUS_BAD_PARAM

Input OpTensor descriptor passed is invalid.
4.74. cudnnGetCTCLossWorkspaceSize
cudnnStatus_t cudnnGetCTCLossWorkspaceSize(
cudnnHandle_t handle,
const cudnnTensorDescriptor_t probsDesc,
const cudnnTensorDescriptor_t gradientsDesc,
const int *labels,
const int *labelLengths,
const int *inputLengths,
cudnnCTCLossAlgo_t algo,
const cudnnCTCLossDescriptor_t ctcLossDesc,
size_t *sizeInBytes)
This function returns the amount of GPU memory workspace the user needs to allocate to be able to call cudnnCTCLoss
with the specified algorithm. The workspace allocated will then be passed to the routine cudnnCTCLoss
.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 probsDesc

Input. Handle to the previously initialized probabilities tensor descriptor.
 gradientsDesc

Input. Handle to a previously initialized gradients tensor descriptor.
 labels

Input. Pointer to a previously initialized labels list.
 labelLengths

Input. Pointer to a previously initialized lengths list, to walk the above labels list.
 inputLengths

Input. Pointer to a previously initialized list of the lengths of the timing steps in each batch.
 algo

Input. Enumerant that specifies the chosen CTC loss algorithm
 ctcLossDesc

Input. Handle to the previously initialized CTC loss descriptor.
 sizeInBytes

Output. Amount of GPU memory needed as workspace to be able to execute the CTC loss computation with the specified
algo
.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The dimensions of probsDesc do not match the dimensions of gradientsDesc.
 The inputLengths do not agree with the first dimension of probsDesc.
 The workSpaceSizeInBytes is not sufficient.
 The labelLengths is greater than 256.

CUDNN_STATUS_NOT_SUPPORTED

A compute or data type other than FLOAT was chosen, or an unknown algorithm type was chosen.
4.75. cudnnGetCallback
cudnnStatus_t cudnnGetCallback(
unsigned mask,
void **udata,
cudnnCallback_t fptr)
(New for 7.1)
This function queries the internal states of cuDNN error reporting functionality.
Parameters
 mask

Output. Pointer to the address where the current internal error reporting message bit mask will be outputted.
 udata

Output. Pointer to the address where the current internally stored udata address will be stored.
 fptr

Output. Pointer to the address where the current internally stored callback function pointer will be stored. When the builtin default callback function is used, NULL will be outputted.
Returns

CUDNN_STATUS_SUCCESS

The function launched successfully.

CUDNN_STATUS_BAD_PARAM

If any of the input parameters are NULL.
4.76. cudnnGetConvolution2dDescriptor
cudnnStatus_t cudnnGetConvolution2dDescriptor(
const cudnnConvolutionDescriptor_t convDesc,
int *pad_h,
int *pad_w,
int *u,
int *v,
int *dilation_h,
int *dilation_w,
cudnnConvolutionMode_t *mode,
cudnnDataType_t *computeType)
This function queries a previously initialized 2D convolution descriptor object.
Parameters
 convDesc

Input/Output. Handle to a previously created convolution descriptor.
 pad_h

Output. zeropadding height: number of rows of zeros implicitly concatenated onto the top and onto the bottom of input images.
 pad_w

Output. zeropadding width: number of columns of zeros implicitly concatenated onto the left and onto the right of input images.
 u

Output. Vertical filter stride.
 v

Output. Horizontal filter stride.
 dilation_h

Output. Filter height dilation.
 dilation_w

Output. Filter width dilation.
 mode

Output. Convolution mode.
 computeType

Output. Compute precision.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The operation was successful.

CUDNN_STATUS_BAD_PARAM

The parameter
convDesc
is nil.
4.77. cudnnGetConvolution2dForwardOutputDim
cudnnStatus_t cudnnGetConvolution2dForwardOutputDim(
const cudnnConvolutionDescriptor_t convDesc,
const cudnnTensorDescriptor_t inputTensorDesc,
const cudnnFilterDescriptor_t filterDesc,
int *n,
int *c,
int *h,
int *w)
This function returns the dimensions of the resulting 4D tensor of a 2D convolution, given the convolution descriptor, the input tensor descriptor and the filter descriptor This function can help to setup the output tensor and allocate the proper amount of memory prior to launch the actual convolution.
Each dimension h and w
of the output images is computed as followed:
outputDim = 1 + ( inputDim + 2*pad  (((filterDim1)*dilation)+1) )/convolutionStride;
The dimensions provided by this routine must be strictly respected when calling cudnnConvolutionForward()
or cudnnConvolutionBackwardBias()
. Providing a smaller or larger output tensor is not supported by the convolution routines.
Parameters
 convDesc

Input. Handle to a previously created convolution descriptor.
 inputTensorDesc

Input. Handle to a previously initialized tensor descriptor.
 filterDesc

Input. Handle to a previously initialized filter descriptor.
 n

Output. Number of output images.
 c

Output. Number of output feature maps per image.
 h

Output. Height of each output feature map.
 w

Output. Width of each output feature map.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_BAD_PARAM

One or more of the descriptors has not been created correctly or there is a mismatch between the feature maps of
inputTensorDesc
andfilterDesc
. 
CUDNN_STATUS_SUCCESS

The object was set successfully.
4.78. cudnnGetConvolutionBackwardDataAlgorithm
cudnnStatus_t cudnnGetConvolutionBackwardDataAlgorithm(
cudnnHandle_t handle,
const cudnnFilterDescriptor_t wDesc,
const cudnnTensorDescriptor_t dyDesc,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnTensorDescriptor_t dxDesc,
cudnnConvolutionBwdDataPreference_t preference,
size_t memoryLimitInBytes,
cudnnConvolutionBwdDataAlgo_t *algo)
This function serves as a heuristic for obtaining the best suited algorithm for cudnnConvolutionBackwardData
for the given layer specifications. Based on the input preference, this function will either return the fastest algorithm or the fastest algorithm within a given memory limit. For an exhaustive search for the fastest algorithm, please use cudnnFindConvolutionBackwardDataAlgorithm
.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 wDesc

Input. Handle to a previously initialized filter descriptor.
 dyDesc

Input. Handle to the previously initialized input differential tensor descriptor.
 convDesc

Input. Previously initialized convolution descriptor.
 dxDesc

Input. Handle to the previously initialized output tensor descriptor.
 preference

Input. Enumerant to express the preference criteria in terms of memory requirement and speed.
 memoryLimitInBytes

Input. It is to specify the maximum amount of GPU memory the user is willing to use as a workspace. This is currently a placeholder and is not used.
 algo

Output. Enumerant that specifies which convolution algorithm should be used to compute the results according to the specified preference
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The numbers of feature maps of the input tensor and output tensor differ.
 The
dataType
of the two tensor descriptors or the filter are different.
4.79. cudnnGetConvolutionBackwardDataAlgorithmMaxCount
cudnnStatus_t cudnnGetConvolutionBackwardDataAlgorithmMaxCount(
cudnnHandle_t handle,
int *count)
This function returns the maximum number of algorithms which can be returned from cudnnFindConvolutionBackwardDataAlgorithm() and cudnnGetConvolutionForwardAlgorithm_v7(). This is the sum of all algorithms plus the sum of all algorithms with Tensor Core operations supported for the current device.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 count

Output. The resulting maximum number of algorithms.
Returns

CUDNN_STATUS_SUCCESS

The function was successful.

CUDNN_STATUS_BAD_PARAM

The provided handle is not allocated properly.
4.80. cudnnGetConvolutionBackwardDataAlgorithm_v7
cudnnStatus_t cudnnGetConvolutionBackwardDataAlgorithm_v7(
cudnnHandle_t handle,
const cudnnFilterDescriptor_t wDesc,
const cudnnTensorDescriptor_t dyDesc,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnTensorDescriptor_t dxDesc,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnConvolutionBwdDataAlgoPerf_t *perfResults)
This function serves as a heuristic for obtaining the best suited algorithm for cudnnConvolutionBackwardData
for the given layer specifications. This function will return all algorithms (including CUDNN_TENSOR_OP_MATH and CUDNN_DEFAULT_MATH versions of algorithms where CUDNN_TENSOR_OP_MATH may be available) sorted by expected (based on internal heuristic) relative performance with fastest being index 0 of perfResults. For an exhaustive search for the fastest algorithm, please use cudnnFindConvolutionBackwardDataAlgorithm
. The total number of resulting algorithms can be queried through the API cudnnGetConvolutionBackwardMaxCount()
.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 wDesc

Input. Handle to a previously initialized filter descriptor.
 dyDesc

Input. Handle to the previously initialized input differential tensor descriptor.
 convDesc

Input. Previously initialized convolution descriptor.
 dxDesc

Input. Handle to the previously initialized output tensor descriptor.
 requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the parameters handle, wDesc, dyDesc, convDesc, dxDesc, perfResults, returnedAlgoCount is NULL.
 The numbers of feature maps of the input tensor and output tensor differ.
 The
dataType
of the two tensor descriptors or the filter are different.  requestedAlgoCount is less than or equal to 0.
4.81. cudnnGetConvolutionBackwardDataWorkspaceSize
cudnnStatus_t cudnnGetConvolutionBackwardDataWorkspaceSize(
cudnnHandle_t handle,
const cudnnFilterDescriptor_t wDesc,
const cudnnTensorDescriptor_t dyDesc,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnTensorDescriptor_t dxDesc,
cudnnConvolutionBwdDataAlgo_t algo,
size_t *sizeInBytes)
This function returns the amount of GPU memory workspace the user needs to allocate to be able to call cudnnConvolutionBackwardData
with the specified algorithm. The workspace allocated will then be passed to the routine cudnnConvolutionBackwardData
. The specified algorithm can be the result of the call to cudnnGetConvolutionBackwardDataAlgorithm
or can be chosen arbitrarily by the user. Note that not every algorithm is available for every configuration of the input tensor and/or every configuration of the convolution descriptor.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 wDesc

Input. Handle to a previously initialized filter descriptor.
 dyDesc

Input. Handle to the previously initialized input differential tensor descriptor.
 convDesc

Input. Previously initialized convolution descriptor.
 dxDesc

Input. Handle to the previously initialized output tensor descriptor.
 algo

Input. Enumerant that specifies the chosen convolution algorithm
 sizeInBytes

Output. Amount of GPU memory needed as workspace to be able to execute a forward convolution with the specified
algo
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The numbers of feature maps of the input tensor and output tensor differ.
 The
dataType
of the two tensor descriptors or the filter are different.

CUDNN_STATUS_NOT_SUPPORTED

The combination of the tensor descriptors, filter descriptor and convolution descriptor is not supported for the specified algorithm.
4.82. cudnnGetConvolutionBackwardFilterAlgorithm
cudnnStatus_t cudnnGetConvolutionBackwardFilterAlgorithm(
cudnnHandle_t handle,
const cudnnTensorDescriptor_t xDesc,
const cudnnTensorDescriptor_t dyDesc,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnFilterDescriptor_t dwDesc,
cudnnConvolutionBwdFilterPreference_t preference,
size_t memoryLimitInBytes,
cudnnConvolutionBwdFilterAlgo_t *algo)
This function serves as a heuristic for obtaining the best suited algorithm for cudnnConvolutionBackwardFilter
for the given layer specifications. Based on the input preference, this function will either return the fastest algorithm or the fastest algorithm within a given memory limit. For an exhaustive search for the fastest algorithm, please use cudnnFindConvolutionBackwardFilterAlgorithm
.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 xDesc

Input. Handle to the previously initialized input tensor descriptor.
 dyDesc

Input. Handle to the previously initialized input differential tensor descriptor.
 convDesc

Input. Previously initialized convolution descriptor.
 dwDesc

Input. Handle to a previously initialized filter descriptor.
 preference

Input. Enumerant to express the preference criteria in terms of memory requirement and speed.
 memoryLimitInBytes

Input. It is to specify the maximum amount of GPU memory the user is willing to use as a workspace. This is currently a placeholder and is not used.
 algo

Output. Enumerant that specifies which convolution algorithm should be used to compute the results according to the specified preference.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The numbers of feature maps of the input tensor and output tensor differ.
 The
dataType
of the two tensor descriptors or the filter are different.
4.83. cudnnGetConvolutionBackwardFilterAlgorithmMaxCount
cudnnStatus_t cudnnGetConvolutionBackwardFilterAlgorithmMaxCount(
cudnnHandle_t handle,
int *count)
This function returns the maximum number of algorithms which can be returned from cudnnFindConvolutionBackwardFilterAlgorithm() and cudnnGetConvolutionForwardAlgorithm_v7(). This is the sum of all algorithms plus the sum of all algorithms with Tensor Core operations supported for the current device.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 count

Output. The resulting maximum count of algorithms.
Returns

CUDNN_STATUS_SUCCESS

The function was successful.

CUDNN_STATUS_BAD_PARAM

The provided handle is not allocated properly.
4.84. cudnnGetConvolutionBackwardFilterAlgorithm_v7
cudnnStatus_t cudnnGetConvolutionBackwardFilterAlgorithm_v7(
cudnnHandle_t handle,
const cudnnTensorDescriptor_t xDesc,
const cudnnTensorDescriptor_t dyDesc,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnFilterDescriptor_t dwDesc,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnConvolutionBwdFilterAlgoPerf_t *perfResults)
This function serves as a heuristic for obtaining the best suited algorithm for cudnnConvolutionBackwardFilter
for the given layer specifications. This function will return all algorithms (including CUDNN_TENSOR_OP_MATH and CUDNN_DEFAULT_MATH versions of algorithms where CUDNN_TENSOR_OP_MATH may be available) sorted by expected (based on internal heuristic) relative performance with fastest being index 0 of perfResults. For an exhaustive search for the fastest algorithm, please use cudnnFindConvolutionBackwardFilterAlgorithm
. The total number of resulting algorithms can be queried through the API cudnnGetConvolutionBackwardMaxCount()
.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 xDesc

Input. Handle to the previously initialized input tensor descriptor.
 dyDesc

Input. Handle to the previously initialized input differential tensor descriptor.
 convDesc

Input. Previously initialized convolution descriptor.
 dwDesc

Input. Handle to a previously initialized filter descriptor.
 requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the parameters handle, xDesc, dyDesc, convDesc, dwDesc, perfResults, returnedAlgoCount is NULL.
 The numbers of feature maps of the input tensor and output tensor differ.
 The
dataType
of the two tensor descriptors or the filter are different.  requestedAlgoCount is less than or equal to 0.
4.85. cudnnGetConvolutionBackwardFilterWorkspaceSize
cudnnStatus_t cudnnGetConvolutionBackwardFilterWorkspaceSize(
cudnnHandle_t handle,
const cudnnTensorDescriptor_t xDesc,
const cudnnTensorDescriptor_t dyDesc,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnFilterDescriptor_t dwDesc,
cudnnConvolutionBwdFilterAlgo_t algo,
size_t *sizeInBytes)
This function returns the amount of GPU memory workspace the user needs to allocate to be able to call cudnnConvolutionBackwardFilter
with the specified algorithm. The workspace allocated will then be passed to the routine cudnnConvolutionBackwardFilter
. The specified algorithm can be the result of the call to cudnnGetConvolutionBackwardFilterAlgorithm
or can be chosen arbitrarily by the user. Note that not every algorithm is available for every configuration of the input tensor and/or every configuration of the convolution descriptor.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 xDesc

Input. Handle to the previously initialized input tensor descriptor.
 dyDesc

Input. Handle to the previously initialized input differential tensor descriptor.
 convDesc

Input. Previously initialized convolution descriptor.
 dwDesc

Input. Handle to a previously initialized filter descriptor.
 algo

Input. Enumerant that specifies the chosen convolution algorithm.
 sizeInBytes

Output. Amount of GPU memory needed as workspace to be able to execute a forward convolution with the specified
algo
.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The numbers of feature maps of the input tensor and output tensor differ.
 The
dataType
of the two tensor descriptors or the filter are different.

CUDNN_STATUS_NOT_SUPPORTED

The combination of the tensor descriptors, filter descriptor and convolution descriptor is not supported for the specified algorithm.
4.86. cudnnGetConvolutionForwardAlgorithm
cudnnStatus_t cudnnGetConvolutionForwardAlgorithm(
cudnnHandle_t handle,
const cudnnTensorDescriptor_t xDesc,
const cudnnFilterDescriptor_t wDesc,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnTensorDescriptor_t yDesc,
cudnnConvolutionFwdPreference_t preference,
size_t memoryLimitInBytes,
cudnnConvolutionFwdAlgo_t *algo)
This function serves as a heuristic for obtaining the best suited algorithm for cudnnConvolutionForward
for the given layer specifications. Based on the input preference, this function will either return the fastest algorithm or the fastest algorithm within a given memory limit. For an exhaustive search for the fastest algorithm, please use cudnnFindConvolutionForwardAlgorithm
.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 xDesc

Input. Handle to the previously initialized input tensor descriptor.
 wDesc

Input. Handle to a previously initialized convolution filter descriptor.
 convDesc

Input. Previously initialized convolution descriptor.
 yDesc

Input. Handle to the previously initialized output tensor descriptor.
 preference

Input. Enumerant to express the preference criteria in terms of memory requirement and speed.
 memoryLimitInBytes

Input. It is used when enumerant
preference
is set toCUDNN_CONVOLUTION_FWD_SPECIFY_WORKSPACE_LIMIT
to specify the maximum amount of GPU memory the user is willing to use as a workspace  algo

Output. Enumerant that specifies which convolution algorithm should be used to compute the results according to the specified preference
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the parameters handle, xDesc, wDesc, convDesc, yDesc is NULL.
 Either yDesc or wDesc have different dimensions from xDesc.
 The data types of tensors xDesc, yDesc or wDesc are not all the same.
 The number of feature maps in xDesc and wDesc differs.
 The tensor xDesc has a dimension smaller than 3.
4.87. cudnnGetConvolutionForwardAlgorithmMaxCount
cudnnStatus_t cudnnGetConvolutionForwardAlgorithmMaxCount(
cudnnHandle_t handle,
int *count)
This function returns the maximum number of algorithms which can be returned from cudnnFindConvolutionForwardAlgorithm() and cudnnGetConvolutionForwardAlgorithm_v7(). This is the sum of all algorithms plus the sum of all algorithms with Tensor Core operations supported for the current device.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 count

Output. The resulting maximum number of algorithms.
Returns

CUDNN_STATUS_SUCCESS

The function was successful.

CUDNN_STATUS_BAD_PARAM

The provided handle is not allocated properly.
4.88. cudnnGetConvolutionForwardAlgorithm_v7
cudnnStatus_t cudnnGetConvolutionForwardAlgorithm_v7(
cudnnHandle_t handle,
const cudnnTensorDescriptor_t xDesc,
const cudnnFilterDescriptor_t wDesc,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnTensorDescriptor_t yDesc,
const int requestedAlgoCount,
int *returnedAlgoCount,
cudnnConvolutionFwdAlgoPerf_t *perfResults)
This function serves as a heuristic for obtaining the best suited algorithm for cudnnConvolutionForward
for the given layer specifications. This function will return all algorithms (including CUDNN_TENSOR_OP_MATH and CUDNN_DEFAULT_MATH versions of algorithms where CUDNN_TENSOR_OP_MATH may be available) sorted by expected (based on internal heuristic) relative performance with fastest being index 0 of perfResults. For an exhaustive search for the fastest algorithm, please use cudnnFindConvolutionForwardAlgorithm
. The total number of resulting algorithms can be queried through the API cudnnGetConvolutionForwardMaxCount()
.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 xDesc

Input. Handle to the previously initialized input tensor descriptor.
 wDesc

Input. Handle to a previously initialized convolution filter descriptor.
 convDesc

Input. Previously initialized convolution descriptor.
 yDesc

Input. Handle to the previously initialized output tensor descriptor.
 requestedAlgoCount

Input. The maximum number of elements to be stored in perfResults.
 returnedAlgoCount

Output. The number of output elements stored in perfResults.
 perfResults

Output. A userallocated array to store performance metrics sorted ascending by compute time.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the parameters handle, xDesc, wDesc, convDesc, yDesc, perfResults, returnedAlgoCount is NULL.
 Either yDesc or wDesc have different dimensions from xDesc.
 The data types of tensors xDesc, yDesc or wDesc are not all the same.
 The number of feature maps in xDesc and wDesc differs.
 The tensor xDesc has a dimension smaller than 3.
 requestedAlgoCount is less than or equal to 0.
4.89. cudnnGetConvolutionForwardWorkspaceSize
cudnnStatus_t cudnnGetConvolutionForwardWorkspaceSize(
cudnnHandle_t handle,
const cudnnTensorDescriptor_t xDesc,
const cudnnFilterDescriptor_t wDesc,
const cudnnConvolutionDescriptor_t convDesc,
const cudnnTensorDescriptor_t yDesc,
cudnnConvolutionFwdAlgo_t algo,
size_t *sizeInBytes)
This function returns the amount of GPU memory workspace the user needs to allocate to be able to call cudnnConvolutionForward
with the specified algorithm. The workspace allocated will then be passed to the routine cudnnConvolutionForward
. The specified algorithm can be the result of the call to cudnnGetConvolutionForwardAlgorithm
or can be chosen arbitrarily by the user. Note that not every algorithm is available for every configuration of the input tensor and/or every configuration of the convolution descriptor.
Parameters
 handle

Input. Handle to a previously created cuDNN context.
 xDesc

Input. Handle to the previously initialized x tensor descriptor.
 wDesc

Input. Handle to a previously initialized filter descriptor.
 convDesc

Input. Previously initialized convolution descriptor.
 yDesc

Input. Handle to the previously initialized y tensor descriptor.
 algo

Input. Enumerant that specifies the chosen convolution algorithm
 sizeInBytes

Output. Amount of GPU memory needed as workspace to be able to execute a forward convolution with the specified
algo
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the parameters handle, xDesc, wDesc, convDesc, yDesc is NULL.
 The tensor yDesc or wDesc are not of the same dimension as xDesc.
 The tensor xDesc, yDesc or wDesc are not of the same data type.
 The numbers of feature maps of the tensor xDesc and wDesc differ.
 The tensor xDesc has a dimension smaller than 3.

CUDNN_STATUS_NOT_SUPPORTED

The combination of the tensor descriptors, filter descriptor and convolution descriptor is not supported for the specified algorithm.
4.90. cudnnGetConvolutionGroupCount
cudnnStatus_t cudnnGetConvolutionGroupCount(
cudnnConvolutionDescriptor_t convDesc,
int *groupCount)
This function returns the group count specified in the given convolution descriptor.
Returns

CUDNN_STATUS_SUCCESS

The group count was returned successfully.

CUDNN_STATUS_BAD_PARAM

An invalid convolution descriptor was provided.
4.91. cudnnGetConvolutionMathType
cudnnStatus_t cudnnGetConvolutionMathType(
cudnnConvolutionDescriptor_t convDesc,
cudnnMathType_t *mathType)
This function returns the math type specified in a given convolution descriptor.
Returns

CUDNN_STATUS_SUCCESS

The math type was returned successfully.

CUDNN_STATUS_BAD_PARAM

An invalid convolution descriptor was provided.
4.92. cudnnGetConvolutionNdDescriptor
cudnnStatus_t cudnnGetConvolutionNdDescriptor(
const cudnnConvolutionDescriptor_t convDesc,
int arrayLengthRequested,
int *arrayLength,
int padA[],
int filterStrideA[],
int dilationA[],
cudnnConvolutionMode_t *mode,
cudnnDataType_t *dataType)
This function queries a previously initialized convolution descriptor object.
Parameters
 convDesc

Input/Output. Handle to a previously created convolution descriptor.
 arrayLengthRequested

Input. Dimension of the expected convolution descriptor. It is also the minimum size of the arrays
padA
,filterStrideA
anddilationA
in order to be able to hold the results  arrayLength

Output. Actual dimension of the convolution descriptor.
 padA

Output. Array of dimension of at least
arrayLengthRequested
that will be filled with the padding parameters from the provided convolution descriptor.  filterStrideA

Output. Array of dimension of at least
arrayLengthRequested
that will be filled with the filter stride from the provided convolution descriptor.  dilationA

Output. Array of dimension of at least
arrayLengthRequested
that will be filled with the dilation parameters from the provided convolution descriptor.  mode

Output. Convolution mode of the provided descriptor.
 datatype

Output. Datatype of the provided descriptor.
Returns

CUDNN_STATUS_SUCCESS

The query was successfully.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The descriptor
convDesc
is nil.  The
arrayLengthRequest
is negative.
 The descriptor

CUDNN_STATUS_NOT_SUPPORTED

The
arrayLengthRequested
is greater than CUDNN_DIM_MAX2.
4.93. cudnnGetConvolutionNdForwardOutputDim
cudnnStatus_t cudnnGetConvolutionNdForwardOutputDim(
const cudnnConvolutionDescriptor_t convDesc,
const cudnnTensorDescriptor_t inputTensorDesc,
const cudnnFilterDescriptor_t filterDesc,
int nbDims,
int tensorOuputDimA[])
This function returns the dimensions of the resulting nD tensor of a nbDims2
D convolution, given the convolution descriptor, the input tensor descriptor and the filter descriptor This function can help to setup the output tensor and allocate the proper amount of memory prior to launch the actual convolution.
Each dimension of the (nbDims2)D
images of the output tensor is computed as followed:
outputDim = 1 + ( inputDim + 2*pad  (((filterDim1)*dilation)+1) )/convolutionStride;
The dimensions provided by this routine must be strictly respected when calling cudnnConvolutionForward()
or cudnnConvolutionBackwardBias()
. Providing a smaller or larger output tensor is not supported by the convolution routines.
Parameters
 convDesc

Input. Handle to a previously created convolution descriptor.
 inputTensorDesc

Input. Handle to a previously initialized tensor descriptor.
 filterDesc

Input. Handle to a previously initialized filter descriptor.
 nbDims

Input. Dimension of the output tensor
 tensorOuputDimA

Output. Array of dimensions
nbDims
that contains on exit of this routine the sizes of the output tensor
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the parameters
convDesc
,inputTensorDesc,
andfilterDesc,
is nil  The dimension of the filter descriptor
filterDesc
is different from the dimension of input tensor descriptorinputTensorDesc
.  The dimension of the convolution descriptor is different from the dimension of input tensor descriptor
inputTensorDesc
2 .  The features map of the filter descriptor
filterDesc
is different from the one of input tensor descriptorinputTensorDesc
.  The size of the dilated filter
filterDesc
is larger than the padded sizes of the input tensor.  The dimension
nbDims
of the output array is negative or greater than the dimension of input tensor descriptorinputTensorDesc
.
 One of the parameters

CUDNN_STATUS_SUCCESS

The routine exits successfully.
4.94. cudnnGetCudartVersion
size_t cudnnGetCudartVersion()
The same version of a given cuDNN library can be compiled against different CUDA Toolkit versions. This routine returns the CUDA Toolkit version that the currently used cuDNN library has been compiled against.
4.95. cudnnGetDropoutDescriptor
cudnnStatus_t cudnnGetDropoutDescriptor(
cudnnDropoutDescriptor_t dropoutDesc,
cudnnHandle_t handle,
float *dropout,
void **states,
unsigned long long *seed)
This function queries the fields of a previously initialized dropout descriptor.
Parameters
 dropoutDesc

Input. Previously initialized dropout descriptor.
 handle

Input. Handle to a previously created cuDNN context.
 dropout

Output. The probability with which the value from input is set to 0 during the dropout layer.
 states

Output. Pointer to userallocated GPU memory that holds random number generator states.
 seed

Output. Seed used to initialize random number generator states.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The call was successful.

CUDNN_STATUS_BAD_PARAM

One or more of the arguments was an invalid pointer.
4.96. cudnnGetErrorString
const char * cudnnGetErrorString(cudnnStatus_t status)
This function converts the cuDNN status code to a NUL terminated (ASCIIZ) static string. For example, when the input argument is CUDNN_STATUS_SUCCESS, the returned string is "CUDNN_STATUS_SUCCESS". When an invalid status value is passed to the function, the returned string is "CUDNN_UNKNOWN_STATUS".
Parameters
 status

Input. cuDNN enumerated status code.
Returns
Pointer to a static, NUL terminated string with the status name.
4.97. cudnnGetFilter4dDescriptor
cudnnStatus_t cudnnGetFilter4dDescriptor(
const cudnnFilterDescriptor_t filterDesc,
cudnnDataType_t *dataType,
cudnnTensorFormat_t *format,
int *k,
int *c,
int *h,
int *w)
This function queries the parameters of the previouly initialized filter descriptor object.
Parameters
 filterDesc

Input. Handle to a previously created filter descriptor.
 datatype

Output. Data type.
 format

Output. Type of format.
 k

Output. Number of output feature maps.
 c

Output. Number of input feature maps.
 h

Output. Height of each filter.
 w

Output. Width of each filter.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The object was set successfully.
4.98. cudnnGetFilterNdDescriptor
cudnnStatus_t cudnnGetFilterNdDescriptor(
const cudnnFilterDescriptor_t wDesc,
int nbDimsRequested,
cudnnDataType_t *dataType,
cudnnTensorFormat_t *format,
int *nbDims,
int filterDimA[])
This function queries a previously initialized filter descriptor object.
Parameters
 wDesc

Input. Handle to a previously initialized filter descriptor.
 nbDimsRequested

Input. Dimension of the expected filter descriptor. It is also the minimum size of the arrays
filterDimA
in order to be able to hold the results  datatype

Output. Data type.
 format

Output. Type of format.
 nbDims

Output. Actual dimension of the filter.
 filterDimA

Output. Array of dimension of at least
nbDimsRequested
that will be filled with the filter parameters from the provided filter descriptor.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The object was set successfully.

CUDNN_STATUS_BAD_PARAM

The parameter
nbDimsRequested
is negative.
4.99. cudnnGetLRNDescriptor
cudnnStatus_t cudnnGetLRNDescriptor(
cudnnLRNDescriptor_t normDesc,
unsigned *lrnN,
double *lrnAlpha,
double *lrnBeta,
double *lrnK)
This function retrieves values stored in the previously initialized LRN descriptor object.
Parameters
 normDesc

Output. Handle to a previously created LRN descriptor.
 lrnN, lrnAlpha, lrnBeta, lrnK

Output. Pointers to receive values of parameters stored in the descriptor object. See cudnnSetLRNDescriptor for more details. Any of these pointers can be NULL (no value is returned for the corresponding parameter).
Possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

Function completed successfully.
4.100. cudnnGetOpTensorDescriptor
cudnnStatus_t cudnnGetOpTensorDescriptor(
const cudnnOpTensorDescriptor_t opTensorDesc,
cudnnOpTensorOp_t *opTensorOp,
cudnnDataType_t *opTensorCompType,
cudnnNanPropagation_t *opTensorNanOpt)
This function returns configuration of the passed Tensor Pointwise math descriptor.
Parameters
 opTensorDesc

Input. Tensor Pointwise math descriptor passed, to get the configuration from.
 opTensorOp

Output. Pointer to the Tensor Pointwise math operation type, associated with this Tensor Pointwise math descriptor.
 opTensorCompType

Output. Pointer to the cuDNN datatype associated with this Tensor Pointwise math descriptor.
 opTensorNanOpt

Output. Pointer to the NAN propagation option associated with this Tensor Pointwise math descriptor.
Returns

CUDNN_STATUS_SUCCESS

The function returned successfully.

CUDNN_STATUS_BAD_PARAM

Input Tensor Pointwise math descriptor passed is invalid.
4.101. cudnnGetPooling2dDescriptor
cudnnStatus_t cudnnGetPooling2dDescriptor(
const cudnnPoolingDescriptor_t poolingDesc,
cudnnPoolingMode_t *mode,
cudnnNanPropagation_t *maxpoolingNanOpt,
int *windowHeight,
int *windowWidth,
int *verticalPadding,
int *horizontalPadding,
int *verticalStride,
int *horizontalStride)
This function queries a previously created 2D pooling descriptor object.
Parameters
 poolingDesc

Input. Handle to a previously created pooling descriptor.
 mode

Output. Enumerant to specify the pooling mode.
 maxpoolingNanOpt

Output. Enumerant to specify the Nan propagation mode.
 windowHeight

Output. Height of the pooling window.
 windowWidth

Output. Width of the pooling window.
 verticalPadding

Output. Size of vertical padding.
 horizontalPadding

Output. Size of horizontal padding.
 verticalStride

Output. Pooling vertical stride.
 horizontalStride

Output. Pooling horizontal stride.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The object was set successfully.
4.102. cudnnGetPooling2dForwardOutputDim
cudnnStatus_t cudnnGetPooling2dForwardOutputDim(
const cudnnPoolingDescriptor_t poolingDesc,
const cudnnTensorDescriptor_t inputDesc,
int *outN,
int *outC,
int *outH,
int *outW)
This function provides the output dimensions of a tensor after 2d pooling has been applied
Each dimension h and w
of the output images is computed as followed:
outputDim = 1 + (inputDim + 2*padding  windowDim)/poolingStride;
Parameters
 poolingDesc

Input. Handle to a previously inititalized pooling descriptor.
 inputDesc

Input. Handle to the previously initialized input tensor descriptor.
 N

Output. Number of images in the output.
 C

Output. Number of channels in the output.
 H

Output. Height of images in the output.
 W

Output. Width of images in the output.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The function launched successfully.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
poolingDesc
has not been initialized.poolingDesc
orinputDesc
has an invalid number of dimensions (2 and 4 respectively are required).
4.103. cudnnGetPoolingNdDescriptor
cudnnStatus_t cudnnGetPoolingNdDescriptor(
const cudnnPoolingDescriptor_t poolingDesc,
int nbDimsRequested,
cudnnPoolingMode_t *mode,
cudnnNanPropagation_t *maxpoolingNanOpt,
int *nbDims,
int windowDimA[],
int paddingA[],
int strideA[])
This function queries a previously initialized generic pooling descriptor object.
Parameters
 poolingDesc

Input. Handle to a previously created pooling descriptor.
 nbDimsRequested

Input. Dimension of the expected pooling descriptor. It is also the minimum size of the arrays
windowDimA
,paddingA
andstrideA
in order to be able to hold the results.  mode

Output. Enumerant to specify the pooling mode.
 maxpoolingNanOpt

Input. Enumerant to specify the Nan propagation mode.
 nbDims

Output. Actual dimension of the pooling descriptor.
 windowDimA

Output. Array of dimension of at least
nbDimsRequested
that will be filled with the window parameters from the provided pooling descriptor.  paddingA

Output. Array of dimension of at least
nbDimsRequested
that will be filled with the padding parameters from the provided pooling descriptor.  strideA

Output. Array of dimension at least
nbDimsRequested
that will be filled with the stride parameters from the provided pooling descriptor.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The object was queried successfully.

CUDNN_STATUS_NOT_SUPPORTED

The parameter
nbDimsRequested
is greater than CUDNN_DIM_MAX.
4.104. cudnnGetPoolingNdForwardOutputDim
cudnnStatus_t cudnnGetPoolingNdForwardOutputDim(
const cudnnPoolingDescriptor_t poolingDesc,
const cudnnTensorDescriptor_t inputDesc,
int nbDims,
int outDimA[])
This function provides the output dimensions of a tensor after Nd pooling has been applied
Each dimension of the (nbDims2)D
images of the output tensor is computed as followed:
outputDim = 1 + (inputDim + 2*padding  windowDim)/poolingStride;
Parameters
 poolingDesc

Input. Handle to a previously inititalized pooling descriptor.
 inputDesc

Input. Handle to the previously initialized input tensor descriptor.
 nbDims

Input. Number of dimensions in which pooling is to be applied.
 outDimA

Output. Array of nbDims output dimensions.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The function launched successfully.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
poolingDesc
has not been initialized. The value of
nbDims
is inconsistent with the dimensionality ofpoolingDesc
andinputDesc
.
4.105. cudnnGetProperty
cudnnStatus_t cudnnGetProperty(
libraryPropertyType type,
int *value)
This function writes a specific part of the cuDNN library version number into the provided host storage.
Parameters
 type

Input. Enumerated type that instructs the function to report the numerical value of the cuDNN major version, minor version, or the patch level.
 value

Output. Host pointer where the version information should be written.
Returns

CUDNN_STATUS_INVALID_VALUE

Invalid value of the
type
argument. 
CUDNN_STATUS_SUCCESS

Version information was stored successfully at the provided address.
4.106. cudnnGetRNNDataDescriptor
cudnnStatus_t cudnnGetRNNDataDescriptor(
cudnnRNNDataDescriptor_t RNNDataDesc,
cudnnDataType_t *dataType,
cudnnRNNDataLayout_t *layout,
int *maxSeqLength,
int *batchSize,
int *vectorSize,
int arrayLengthRequested,
int seqLengthArray[],
void *paddingFill);
This function retrieves a previously created RNN data descriptor object.
Parameters
 RNNDataDesc

Input. A previously created and initialized RNN descriptor.
 dataType

Output. Pointer to the host memory location to store the datatype of the RNN data tensor.
 layout

Output. Pointer to the host memory location to store the memory layout of the RNN data tensor.
 maxSeqLength

Output. The maximum sequence length within this RNN data tensor, including the padding vectors.
 batchSize

Output. The number of sequences within the minibatch.
 vectorSize

Output. The vector length (i.e. embedding size) of the input or output tensor at each timestep.
 arrayLengthRequested

Input. The number of elements that the user requested for
seqLengthArray
.  seqLengthArray

Output. Pointer to the host memory location to store the integer array describing the length (i.e. number of timesteps) of each sequence. This is allowed to be a NULL pointer if
arrayLengthRequested
is zero.  paddingFill

Output. Pointer to the host memory location to store the user defined symbol. The symbol should be interpreted as the same data type as the RNN data tensor.
Returns

CUDNN_STATUS_SUCCESS

The parameters are fetched successfully.

CUDNN_STATUS_BAD_PARAM

Any one of these have occurred:
 Any of
RNNDataDesc
,dataType
,layout
,maxSeqLength
,batchSize
,vectorSize
,paddingFill
is NULL. seqLengthArray
is NULL whilearrayLengthRequested
is greater than zero.arrayLengthRequested
is less than zero.
 Any of
4.107. cudnnGetRNNDescriptor
cudnnStatus_t cudnnGetRNNDescriptor(
cudnnHandle_t handle,
cudnnRNNDescriptor_t rnnDesc,
int * hiddenSize,
int * numLayers,
cudnnDropoutDescriptor_t * dropoutDesc,
cudnnRNNInputMode_t * inputMode,
cudnnDirectionMode_t * direction,
cudnnRNNMode_t * mode,
cudnnRNNAlgo_t * algo,
cudnnDataType_t * dataType)
This function retrieves RNN network parameters that were configured by cudnnSetRNNDescriptor(). All pointers passed to the function should be notNULL or CUDNN_STATUS_BAD_PARAM is reported. The function does not check the validity of retrieved network parameters. The parameters are verified when they are written to the RNN descriptor.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor.
 rnnDesc

Input. A previously created and initialized RNN descriptor.
 hiddenSize

Output. Pointer where the size of the hidden state should be stored (the same value is used in every layer).
 numLayers

Output. Pointer where the number of RNN layers should be stored.
 dropoutDesc

Output. Pointer where the handle to a previously configured dropout descriptor should be stored.
 inputMode

Output. Pointer where the mode of the first RNN layer should be saved.
 direction

Output. Pointer where RNN unidirectional/bidirectional mode should be saved.
 mode

Output. Pointer where RNN cell type should be saved.
 algo

Output. Pointer where RNN algorithm type should be stored.
 dataType

Output. Pointer where the data type of RNN weights/biases should be stored.
Returns

CUDNN_STATUS_SUCCESS

RNN parameters were successfully retrieved from the RNN descriptor.

CUDNN_STATUS_BAD_PARAM

At least one pointer passed to the cudnnGetRNNDescriptor() function is NULL.
4.108. cudnnGetRNNLinLayerBiasParams
cudnnStatus_t cudnnGetRNNLinLayerBiasParams(
cudnnHandle_t handle,
const cudnnRNNDescriptor_t rnnDesc,
const int pseudoLayer,
const cudnnTensorDescriptor_t xDesc,
const cudnnFilterDescriptor_t wDesc,
const void *w,
const int linLayerID,
cudnnFilterDescriptor_t linLayerBiasDesc,
void **linLayerBias)
This function is used to obtain a pointer and a descriptor of every RNN bias column vector in each pseudolayer within the recurrent network defined by rnnDesc and its input width specified in xDesc
.
The cudnnGetRNNLinLayerBiasParams()
function was changed in cuDNN version 7.1.1 to match the behavior of cudnnGetRNNLinLayerMatrixParams()
.
The cudnnGetRNNLinLayerBiasParams()
function returns the RNN bias vector size in two dimensions: rows and columns. Due to historical reasons, the minimum number of dimensions in the filter descriptor is three. In previous versions of the cuDNN library, the function returned the total number of vector elements in linLayerBiasDesc
as follows: filterDimA[0]=total_size, filterDimA[1]=1, filterDimA[2]=1 (see the description of the cudnnGetFilterNdDescriptor() function). In v7.1.1, the format was changed to: filterDimA[0]=1, filterDimA[1]=rows, filterDimA[2]=1 (number of columns). In both cases, the "format" field of the filter descriptor should be ignored when retrieved by cudnnGetFilterNdDescriptor()
. Note that the RNN implementation in cuDNN uses two bias vectors before the cell nonlinear function (see equations in Chapter 3 describing the cudnnRNNMode_t
enumerated type).
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor.
 rnnDesc

Input. A previously initialized RNN descriptor.
 pseudoLayer

Input. The pseudolayer to query. In unidirectional RNNs, a pseudolayer is the same as a "physical" layer (pseudoLayer=0 is the RNN input layer, pseudoLayer=1 is the first hidden layer). In bidirectional RNNs there are twice as many pseudolayers in comparison to "physical" layers (pseudoLayer=0 and pseudoLayer=1 are both input layers; pseudoLayer=0 refers to the forward part and pseudoLayer=1 refers to the backward part of the "physical" input layer; pseudoLayer=2 is the forward part of the first hidden layer, and so on).
 xDesc

Input. A fully packed tensor descriptor describing the input to one recurrent iteration (to retrieve the RNN input width).
 wDesc

Input. Handle to a previously initialized filter descriptor describing the weights for the RNN.
 w

Input. Data pointer to GPU memory associated with the filter descriptor
wDesc
.  linLayerID

Input. The linear layer to obtain information about:
 If
mode
inrnnDesc
was set toCUDNN_RNN_RELU
orCUDNN_RNN_TANH
a value of 0 references the bias applied to the input from the previous layer, a value of 1 references the bias applied to the recurrent input.  If
mode
inrnnDesc
was set toCUDNN_LSTM
values of 0, 1, 2 and 3 reference bias applied to the input from the previous layer, value of 4, 5, 6 and 7 reference bias applied to the recurrent input. Values 0 and 4 reference the input gate.
 Values 1 and 5 reference the forget gate.
 Values 2 and 6 reference the new memory gate.
 Values 3 and 7 reference the output gate.
 If
mode
inrnnDesc
was set toCUDNN_GRU
values of 0, 1 and 2 reference bias applied to the input from the previous layer, value of 3, 4 and 5 reference bias applied to the recurrent input. Values 0 and 3 reference the reset gate.
 Values 1 and 4 reference the update gate.
 Values 2 and 5 reference the new memory gate.
 If
 linLayerBiasDesc

Output. Handle to a previously created filter descriptor.
 linLayerBias

Output. Data pointer to GPU memory associated with the filter descriptor
linLayerBiasDesc
.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the following arguments is NULL:
handle
,rnnDesc
,xDesc
,wDesc
,linLayerBiasDesc
,linLayerBias
.  A data type mismatch was detected between rnnDesc and other descriptors.
 Minimum requirement for the 'w' pointer alignment is not satisfied.
 The value of
pseudoLayer
orlinLayerID
is out of range.
 One of the following arguments is NULL:

CUDNN_STATUS_INVALID_VALUE

Some elements of the
linLayerBias
vector are be outside the 'w' buffer boundaries as specified by thewDesc
descriptor.
4.109. cudnnGetRNNLinLayerMatrixParams
cudnnStatus_t cudnnGetRNNLinLayerMatrixParams(
cudnnHandle_t handle,
const cudnnRNNDescriptor_t rnnDesc,
const int pseudoLayer,
const cudnnTensorDescriptor_t xDesc,
const cudnnFilterDescriptor_t wDesc,
const void *w,
const int linLayerID,
cudnnFilterDescriptor_t linLayerMatDesc,
void **linLayerMat)
This function is used to obtain a pointer and a descriptor of every RNN weight matrix in each pseudolayer within the recurrent network defined by rnnDesc
and its input width specified in xDesc
.
The cudnnGetRNNLinLayerMatrixParams()
function was enhanced in cuDNN version 7.1.1 without changing its prototype. Instead of reporting the total number of elements in each weight matrix in the “linLayerMatDesc” filter descriptor, the function returns the matrix size as two dimensions: rows and columns. Moreover, when a weight matrix does not exist, e.g due to CUDNN_SKIP_INPUT mode, the function returns NULL in linLayerMat
and all fields of linLayerMatDesc are zero.
The cudnnGetRNNLinLayerMatrixParams()
function returns the RNN matrix size in two dimensions: rows and columns. This allows the user to easily print and initialize RNN weight matrices. Elements in each weight matrix are arranged in the rowmajor order. Due to historical reasons, the minimum number of dimensions in the filter descriptor is three. In previous versions of the cuDNN library, the function returned the total number of weights in linLayerMatDesc as follows: filterDimA[0]=total_size, filterDimA[1]=1, filterDimA[2]=1 (see the description of the cudnnGetFilterNdDescriptor() function). In v7.1.1, the format was changed to: filterDimA[0]=1, filterDimA[1]=rows, filterDimA[2]=columns. In both cases, the "format" field of the filter descriptor should be ignored when retrieved by cudnnGetFilterNdDescriptor()
.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor.
 rnnDesc

Input. A previously initialized RNN descriptor.
 pseudoLayer

Input. The pseudolayer to query. In unidirectional RNNs, a pseudolayer is the same as a "physical" layer (pseudoLayer=0 is the RNN input layer, pseudoLayer=1 is the first hidden layer). In bidirectional RNNs there are twice as many pseudolayers in comparison to "physical" layers (pseudoLayer=0 and pseudoLayer=1 are both input layers; pseudoLayer=0 refers to the forward part and pseudoLayer=1 refers to the backward part of the "physical" input layer; pseudoLayer=2 is the forward part of the first hidden layer, and so on).
 xDesc

Input. A fully packed tensor descriptor describing the input to one recurrent iteration (to retrieve the RNN input width).
 wDesc

Input. Handle to a previously initialized filter descriptor describing the weights for the RNN.
 w

Input. Data pointer to GPU memory associated with the filter descriptor
wDesc
.  linLayerID

Input. The linear layer to obtain information about:
 If
mode
inrnnDesc
was set toCUDNN_RNN_RELU
orCUDNN_RNN_TANH
a value of 0 references the matrix multiplication applied to the input from the previous layer, a value of 1 references the matrix multiplication applied to the recurrent input.  If
mode
inrnnDesc
was set toCUDNN_LSTM
values of 03 reference matrix multiplications applied to the input from the previous layer, value of 47 reference matrix multiplications applied to the recurrent input. Values 0 and 4 reference the input gate.
 Values 1 and 5 reference the forget gate.
 Values 2 and 6 reference the new memory gate.
 Values 3 and 7 reference the output gate.
 Value 8 references the "recurrent" projection matrix when enabled by the cudnnSetRNNProjectionLayers() function.
 If
mode
inrnnDesc
was set toCUDNN_GRU
values of 02 reference matrix multiplications applied to the input from the previous layer, value of 35 reference matrix multiplications applied to the recurrent input. Values 0 and 3 reference the reset gate.
 Values 1 and 4 reference the update gate.
 Values 2 and 5 reference the new memory gate.
 If
 linLayerMatDesc

Output. Handle to a previously created filter descriptor. When the weight matrix does not exist, the returned filer descriptor has all fields set to zero.
 linLayerMat

Output. Data pointer to GPU memory associated with the filter descriptor
linLayerMatDesc
. When the weight matrix does not exist, the returned pointer is NULL.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_NOT_SUPPORTED

The function does not support the provided configuration.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 One of the following arguments is NULL:
handle
,rnnDesc
,xDesc
,wDesc
,linLayerMatDesc
,linLayerMat
.  A data type mismatch was detected between rnnDesc and other descriptors.
 Minimum requirement for the
'w'
pointer alignment is not satisfied.  The value of pseudoLayer or linLayerID is out of range.
 One of the following arguments is NULL:

CUDNN_STATUS_INVALID_VALUE

Some elements of the
linLayerMat
vector are be outside the'w'
buffer boundaries as specified by thewDesc
descriptor.
4.110. cudnnGetRNNParamsSize
cudnnStatus_t cudnnGetRNNParamsSize(
cudnnHandle_t handle,
const cudnnRNNDescriptor_t rnnDesc,
const cudnnTensorDescriptor_t xDesc,
size_t *sizeInBytes,
cudnnDataType_t dataType)
This function is used to query the amount of parameter space required to execute the RNN described by rnnDesc
with inputs dimensions defined by xDesc
.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor.
 rnnDesc

Input. A previously initialized RNN descriptor.
 xDesc

Input. A fully packed tensor descriptor describing the input to one recurrent iteration.
 sizeInBytes

Output. Minimum amount of GPU memory needed as parameter space to be able to execute an RNN with the specified descriptor and input tensors.
 dataType

Input. The data type of the parameters.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The descriptor
rnnDesc
is invalid.  The descriptor
xDesc
is invalid.  The descriptor
xDesc
is not fully packed.  The combination of
dataType
and tensor descriptor data type is invalid.
 The descriptor

CUDNN_STATUS_NOT_SUPPORTED

The combination of the RNN descriptor and tensor descriptors is not supported.
4.111. cudnnGetRNNPaddingMode
cudnnStatus_t cudnnGetRNNPaddingMode(
cudnnRNNDescriptor_t rnnDesc,
cudnnRNNPaddingMode_t *paddingMode)
This function retrieves the RNN padding mode from the RNN descriptor.
Parameters
 rnnDesc

Input/Output. A previously created RNN descriptor.
 *paddingMode

Input. Pointer to the host memory where the RNN padding mode is saved.
Returns

CUDNN_STATUS_SUCCESS

The RNN padding mode parameter was retrieved successfully.

CUDNN_STATUS_BAD_PARAM

Either the
rnnDesc
or*paddingMode
is NULL.
4.112. cudnnGetRNNProjectionLayers
cudnnStatus_t cudnnGetRNNProjectionLayers(
cudnnHandle_t handle,
cudnnRNNDescriptor_t rnnDesc,
int *recProjSize,
int *outProjSize)
(New for 7.1)
This function retrieves the current RNN “projection” parameters. By default the projection feature is disabled so invoking this function immediately after cudnnSetRNNDescriptor() will yield recProjSize equal to hiddenSize and outProjSize set to zero. The cudnnSetRNNProjectionLayers()
method enables the RNN projection.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor.
 rnnDesc

Input. A previously created and initialized RNN descriptor.
 recProjSize

Output. Pointer where the “recurrent” projection size should be stored.
 outProjSize

Output. Pointer where the “output” projection size should be stored.
Returns

CUDNN_STATUS_SUCCESS

RNN projection parameters were retrieved successfully.

CUDNN_STATUS_BAD_PARAM

A NULL pointer was passed to the function.
4.113. cudnnGetRNNTrainingReserveSize
cudnnStatus_t cudnnGetRNNTrainingReserveSize(
cudnnHandle_t handle,
const cudnnRNNDescriptor_t rnnDesc,
const int seqLength,
const cudnnTensorDescriptor_t *xDesc,
size_t *sizeInBytes)
This function is used to query the amount of reserved space required for training the RNN described by rnnDesc
with inputs dimensions defined by xDesc
. The same reserved space buffer must be passed to cudnnRNNForwardTraining
, cudnnRNNBackwardData
and cudnnRNNBackwardWeights
. Each of these calls overwrites the contents of the reserved space, however it can safely be backed up and restored between calls if reuse of the memory is desired.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor.
 rnnDesc

Input. A previously initialized RNN descriptor.
 seqLength

Input. Number of iterations to unroll over. The value of this
seqLength
must not exceed the value that was used incudnnGetRNNWorkspaceSize()
function for querying the workspace size required to execute the RNN.  xDesc

Input. An array of tensor descriptors describing the input to each recurrent iteration (one descriptor per iteration). The first dimension (batch size) of the tensors may decrease from element
n
to elementn+1
but may not increase. Each tensor descriptor must have the same second dimension (vector length).  sizeInBytes

Output. Minimum amount of GPU memory needed as reserve space to be able to train an RNN with the specified descriptor and input tensors.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The descriptor
rnnDesc
is invalid.  At least one of the descriptors in
xDesc
is invalid.  The descriptors in
xDesc
have inconsistent second dimensions, strides or data types.  The descriptors in
xDesc
have increasing first dimensions.  The descriptors in
xDesc
is not fully packed.
 The descriptor

CUDNN_STATUS_NOT_SUPPORTED

The the data types in tensors described by xDesc is not supported.
4.114. cudnnGetRNNWorkspaceSize
cudnnStatus_t cudnnGetRNNWorkspaceSize(
cudnnHandle_t handle,
const cudnnRNNDescriptor_t rnnDesc,
const int seqLength,
const cudnnTensorDescriptor_t *xDesc,
size_t *sizeInBytes)
This function is used to query the amount of work space required to execute the RNN described by rnnDesc
with inputs dimensions defined by xDesc
.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor.
 rnnDesc

Input. A previously initialized RNN descriptor.
 seqLength

Input. Number of iterations to unroll over. Workspace that is allocated, based on the size this function provides, cannot be used for sequences longer than
seqLength
.  xDesc

Input. An array of tensor descriptors describing the input to each recurrent iteration (one descriptor per iteration). The first dimension (batch size) of the tensors may decrease from element
n
to elementn+1
but may not increase. For example, if you have multiple time series in a batch, they can be different lengths. This dimension is the batch size for the particular iteration of the sequence, and so it should decrease when a sequence in the batch has terminated.Each tensor descriptor must have the same second dimension (vector length).
 sizeInBytes

Output. Minimum amount of GPU memory needed as workspace to be able to execute an RNN with the specified descriptor and input tensors.
The possible error values returned by this function and their meanings are listed below.
Returns

CUDNN_STATUS_SUCCESS

The query was successful.

CUDNN_STATUS_BAD_PARAM

At least one of the following conditions are met:
 The descriptor
rnnDesc
is invalid.  At least one of the descriptors in
xDesc
is invalid.  The descriptors in
xDesc
have inconsistent second dimensions, strides or data types.  The descriptors in
xDesc
have increasing first dimensions.  The descriptors in
xDesc
is not fully packed.
 The descriptor

CUDNN_STATUS_NOT_SUPPORTED

The data types in tensors described by xDesc is not supported.
4.115. cudnnGetReduceTensorDescriptor
cudnnStatus_t cudnnGetReduceTensorDescriptor(
const cudnnReduceTensorDescriptor_t reduceTensorDesc,
cudnnReduceTensorOp_t *reduceTensorOp,
cudnnDataType_t *reduceTensorCompType,
cudnnNanPropagation_t *reduceTensorNanOpt,
cudnnReduceTensorIndices_t *reduceTensorIndices,
cudnnIndicesType_t *reduceTensorIndicesType)
This function queries a previously initialized reduce tensor descriptor object.
Parameters
 reduceTensorDesc

Input. Pointer to a previously initialized reduce tensor descriptor object.
 reduceTensorOp

Output. Enumerant to specify the reduce tensor operation.
 reduceTensorCompType

Output. Enumerant to specify the computation datatype of the reduction.
 reduceTensorNanOpt

Input. Enumerant to specify the Nan propagation mode.
 reduceTensorIndices

Output. Enumerant to specify the reduce tensor indices.
 reduceTensorIndicesType

Output. Enumerant to specify the reduce tensor indices type.
Returns

CUDNN_STATUS_SUCCESS

The object was queried successfully.

CUDNN_STATUS_BAD_PARAM

reduceTensorDesc is NULL.
4.116. cudnnGetReductionIndicesSize
cudnnStatus_t cudnnGetReductionIndicesSize(
cudnnHandle_t handle,
const cudnnReduceTensorDescriptor_t reduceDesc,
const cudnnTensorDescriptor_t aDesc,
const cudnnTensorDescriptor_t cDesc,
size_t *sizeInBytes)
This is a helper function to return the minimum size of the index space to be passed to the reduction given the input and output tensors.
Parameters
 handle

Input. Handle to a previously created cuDNN library descriptor.
 reduceDesc

Input. Pointer to a previously initialized reduce tensor descriptor object.
 aDesc

Input. Pointer to the input tensor descriptor.
 cDesc

Input. Pointer to the output tensor descriptor.
 sizeInBytes

Output. Minimum size of the index space to be passed to the reduction.
Returns

CUDNN_STATUS_SUCCESS

The index space size is returned successfully.
4.117. cudnnGetReductionWorkspaceSize
cudnnStatus_t cudnnGetReductionWorkspaceSize(
cudnnHandle_t handle,
const cudnnReduceTensorDescriptor_t reduceDesc,
const cudnnTensorDescriptor_t aDesc,
const cudnnTensorDescriptor_t cDesc,
size_t *sizeInBytes)
This is a helper function to return the minimum size of the workspace to be passed to the reduction given the input and output tensors.
Param