In this post you are going to find what settings you need to configure to enable RSS.

Receive Side Scaling (RSS) enables concurrent processing of received packets from one network adapter by different CPUs on a system.

At boot time, Windows Server 2008 R2 considers the bandwidth and media connection state while allotting CPUs. Higher bandwidth network adapters get more CPUs at startup. Multiple network adapters with the same bandwidth receive the same number of receive-side scaling CPUs.

RSS was included in the Scalable Network Pack for Windows Server 2003, Windows Server 2003 SP2, and Windows Server 2008/Windows Vista. Prior to this, only one CPU could handle the traffic from a given network interface.

Note that this network optimization is configured only at parent partition level and there is no need to configure it inside VMs.

RSS (Receive Side Scaling)

OS Level feature

Collector Script  = AdvancedNet_Features.ps1

Using Receive Side Scaling

 

http://support.microsoft.com/kb/951037/en-us

THIS SETTING MUST BE CONFIGURED ON PARENT PARTITION (Enabled by default on WS08 R2

netsh int tcp show global ( command included on advancedNet_Features.ps1 script)

NIC Adapter Level Feature

Collector Script = AdvancedNet_Features.ps1

 

http://technet.microsoft.com/es-es/library/gg162703(WS.10).aspx

THESE REGISTRY KEYS MUST BE ENABLED ON PARENT PARTITION

 

"\SYSTEM\CurrentControlSet\Control\Class

\{4D36E972-E325-11CE-BFC1-08002BE10318}\xxxx\*RssOrVmqPreference"

 

"\SYSTEM\CurrentControlSet\Control\Class

\{4D36E972-E325-11CE-BFC1-08002BE10318}\xxxx\*MaxRssProcessors"

 

"\SYSTEM\CurrentControlSet\Control\Class

\{4D36E972-E325-11CE-BFC1-08002BE10318}\xxxx\*RssBaseProcNumber"

 

"\SYSTEM\CurrentControlSet\Control\Class

\{4D36E972-E325-11CE-BFC1-08002BE10318}\xxxx\*NUMANodeID"

 

If you are configuring more than one network adapter, each adapter should have a different value assigned to the *RssBaseProcNumber sub-key with sufficient difference so that there are no overlapping RSS processors. For example, if Network Adapter A has a value of 0 assigned to *RssBaseProcNumber and a value of 3 assigned to *MaxRssProcessors, Network Adapter B should have an *RssBaseProcNumber of 4.