The following section describes the registry keys that are only relevant to Ethernet driver.
Value Name | Default Value | Description |
RoceMaxFrameSize | 1024 | The maximum size of a frame (or a packet) that can be sent by the RoCE protocol (a.k.a Maximum Transmission Unit (MTU)). Using larger RoCE MTU will improve the performance; however, one must ensure that the entire system, including switches, supports the defined MTU. Ethernet packet uses the general MTU value, whereas the RoCE packet uses the RoCE MTU The valid values are:
Note: This registry key is supported only in Ethernet drivers. |
*PriorityVLANTag | 3 (Packet Priority & VLAN Enabled) | Enables sending and receiving IEEE 802.3ac tagged frames, which include:
When this feature is enabled, the Mellanox driver supports sending and receiving a packet with VLAN and QoS tag. Note: This register cannot be configured via a VF that is running over Microsoft Hyper-V. |
PromiscuousVlan | 0 | Specifies whether a promiscuous VLAN is enabled or not. When this parameter is set, all the packets with VLAN tags are passed to an upper level without executing any filtering. The valid values are:
Note: This registry value is not exposed via the UI. |
UseRSSForRawIP | 1 | The execution of RSS on UDP and Raw IP packets. In a forwarding scenario, one can improve the performance by disabling RSS on UDP or a raw packet. In such a case, the entire receive processing of these packets is done on the processor that was defined in DefaultRecvRingProcessor registry key. The valid values are:
This is also relevant for IPoIB. Note: This registry value is not exposed via the UI. |
UseRSSForUDP | 1 | Used to execute RSS on UDP and Raw IP packet. In forwarding scenario you can improve the performance by disable RSS on UDP or raw packet. In such a case all the receive processing of these packets is done on the processor that was defined in DefaultRecvRingProcessor registry key. The valid values are:
Note: This registry value is not exposed via UI. |
SingleStream | 0 | It used to get the maximum bandwidth when using single stream traffic. When setting the registry key to enabled the driver will forward the sending packet to another CPU. This decrease the CPU utilization of the sender and allows sending in higher rate The valid values are:
Note: Only relevant for Ethernet and IPoIB |
IgnoreFCS | 0 | The valid values are:
When enabled, the device is configured to:
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This group of registry keys allows the administrator to control the TCP/IP traffic by pausing frame transmitting and/or receiving operations. By enabling the Flow Control mechanism, the adapters can overcome any TCP/IP issues and eliminate the risk of data loss.
Value Name | Default Value | Description |
PerPriRxPause | 0 | When Per Priority Rx Pause is configured, the receiving adapter generates a flow control frame when its priority received queue reaches a pre-defined limit. The flow control frame is sent to the sending adapter. Notes:
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PerPriTxPause | 0 | When Per Priority TX Pause is configured, the sending adapter pauses the transmission of a specific priority, if it receives a flow control frame from a link partner. Notes:
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This section describes the registry keys that are used to control the NDIS Virtual Machine Queue (VMQ). The VMQ supports Microsoft Hyper-V network performance, and is supported on Windows Server 2012, 2012 R2 and 2016.
For more details about VMQ please refer to Microsoft web site, http://msdn.microsoft.com/en-us/library/windows/hardware/ff571034(v=vs.85).aspx
Value Name | Default Value | Description |
*RssOrVmqPreference | 0 | Specifies whether VMQ capabilities should be enabled instead of receive-side scaling (RSS) capabilities. The valid values are:
Note: This registry value is not exposed via the UI. |
*VMQLookaheadSplit | 1 | Specifies whether the driver enables or disables the ability to split the receive buffers into lookahead and post-lookahead buffers. The valid values are:
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*VMQVlanFiltering | 1 | Specifies whether the device enables or disables the ability to filter network packets by using the VLAN identifier in the media access control (MAC) header. The valid values are:
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MaxNumVmqs | 127 | The number of VMQs that the device supports in parallel. This parameter can effect memory consumption of the interface, since for each VMQ, the driver creates a separate receive ring and an allocate buffer for it. In order to minimize the memory consumption, one can reduce the number of VMs that use VMQ in parallel. However, this can affect the performance. The valid values are 1 up to 127. Note: This registry value is not exposed via the UI. |
MaxNumMacAddrFilters | 127 | The number of different MAC addresses that the physical port supports. This registry key affects the number of supported MAC addresses that is reported to the OS. The valid values are 1 up to 127. Note: This registry value is not exposed via the UI. |
MaxNumVlanFilters | 125 | The number of VLANs that are supported for each port. The valid values are 1 up to 127. Note: This registry value is not exposed via the UI. |