User Manual

Rev 4.70
Mellanox Technologies
187
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.
C.6.2 VMQ Options
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 Win-
dows Server 2008 R2 and above.
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
*FlowControl 3 When Rx Pause is enabled, the receiving adapter generates a flow
control frame when its received queue reaches a pre-defined limit.
The flow control frame is sent to the sending adapter.
When TX Pause is enabled, the sending adapter pauses the trans-
mission if it receives a flow control frame from a link partner.
The valid values are:
• 0: Flow control is disabled
• 1: Tx Flow control is Enabled
• 2: Rx Flow control is enabled
• 3: Rx & Tx Flow control is enabled
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:
• This registry value is not exposed via the UI.
• RxPause and PerPriRxPause are mutual exclusive (i.e. at most,
only one of them can be set).
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:
• This registry value is not exposed via the UI.
• TxPause and PerPriTxPause are mutual exclusive (i.e. at most,
only one of them can be set).
Value Name Default Value Description
*VMQ 1 The support for the virtual machine queue (VMQ) features of the
network adapter.
The valid values are:
• 1: enable
• 0: disable