Environment Variables#

This page is intentionally scoped to the capture-and-replay shim (TRT_SHIM_*) documented in Capture and Replay.

It is not a complete index of every environment variable that appears in TensorRT workflows. Variables such as LD_LIBRARY_PATH, PATH, CUDA_VISIBLE_DEVICES, and framework-specific settings are documented where those workflows live (install method pages, samples, and tooling guides).

Use these entry points for other behavior-changing variables:

PATH and LD_LIBRARY_PATH: Installing TensorRT
CUDA_VISIBLE_DEVICES and device selection: Multi-Device Inference
CUDA_MPS_ACTIVE_THREAD_PERCENTAGE: Limiting Compute Resources

The table below lists only TRT_SHIM_* variables.

Capture-and-replay shim (`TRT_SHIM_*`)#

Set these variables before launching an application through the TensorRT capture shim (LD_PRELOAD or drop-in replacement). For setup instructions, refer to Capture and Replay.

Warning

The capture shim is a development and debugging tool. Do not preload it in a production process.

Captured .json and .bin output can contain proprietary model weights in cleartext. Write capture output only to a restricted, non-shared directory, and remove it when debugging is complete.

TRT_SHIM_NVINFER_LIB_NAME controls which native TensorRT library is loaded into the process. Set it only to a trusted, absolute path that is not writable by untrusted users.

Note

TRT_SHIM_OUTPUT_JSON_FILE takes precedence over TRT_SHIM_FORCE_SINGLE_THREAD_API. If both are set, the shim does not enforce single-threaded API calls.

Table 24 `TRT_SHIM_*` environment variables#
Variable	Description	Type	Default
`TRT_SHIM_OUTPUT_JSON_FILE`	Path to save the captured `.json` file. A corresponding `.bin` file is created in the same directory.	`string`	`capture.json`
`TRT_SHIM_NVINFER_LIB_NAME`	Intercepted TensorRT library name. If unset, `dlopen(<lib_name>)` finds the library using its normal search rules (a full path is also allowed).	`string`	`libnvinfer.so`
`TRT_SHIM_DUMP_API`	Print `enter` and `exit` messages for every API function call.	`bool`	`false`
`TRT_SHIM_PRINT_WELCOME`	Print `Welcome` to `TensorRT Shim` at the start of the run.	`bool`	`false`
`TRT_SHIM_FORCE_SINGLE_THREAD_API`	Lock every API call to enforce single-threaded execution. Ignored when `TRT_SHIM_OUTPUT_JSON_FILE` is set.	`bool`	`false`
`TRT_SHIM_INLINE_WEIGHTS_LOWER_EQUAL_THAN`	Inline weights into the `.json` instead of a separate `.bin` when their size (in elements) is ≤ this threshold.	`int`	`8`
`TRT_SHIM_MARK_AS_RANDOM_WEIGHTS_GREATER_EQUAL_THAN`	Skip saving weights with an element count ≥ this threshold (they will be marked as random).	`int`	`Max int`
`TRT_SHIM_FLUSH_AFTER_EVERY_CALL`	Flush captured calls to the file after every API call instead of aggregating them.	`bool`	`false`
`TRT_SHIM_FLUSH_ON_BUILD`	Flush captured calls after every `buildSerializedNetwork` call. Useful for debugging crashes during engine building or for capturing incremental progress in multi-network sessions.	`bool`	`false`
`TRT_SHIM_SET_TACTIC_CACHE`	Path to a tactic-cache file loaded into `IBuilderConfig` so tactic selection stays consistent across runs. Load only a cache from a trusted, integrity-verified artifact location; timing caches can contain JIT-compiled code.	`string`	`""`

Environment Variables#

Capture-and-replay shim (TRT_SHIM_*)#

Capture-and-replay shim (`TRT_SHIM_*`)#