Enabling virtual receive-side scaling (vRSS) in Windows Server 2012 R2 virtual machine

In Windows Server 2012 R2, Microsoft added the receive-side scaling function in a Microsoft Hyper-V Network Adapter of a virtual machine. This function is called virtual receive-side scaling by Microsoft. By default, receive-side scaling in a virtual machine is disabled.  

Before using virtual receive-side scaling, the network throughput of a virtual machine is limited by a single virtual processor because a single virtual processor isn't enough processing power to handle the network throughput larger than 5Gb. Microsoft improved virtual machine queue to work with virtual receive-side scaling in Windows Server 2012 R2. The network traffic of a virtual machine which is enabled vRSS will spread to multiple VMQ. It can improve the network performance of a virtual machine.

To use virtual receive-side scaling, administrators make sure the following items are supported.

• Operating system of a virtual machine is Windows Server 2012 R2 or Windows 8.1
• The Hyper-V host is Windows Server 2012 R2
• Windows Server 2012 R2 integration components is installed in a virtual machine
• A physical network adapter supports Virtual Machine Queue (VMQ)

To enable virtual receive-side scaling, administrators can enable it by "Device Manager" or "PowerShell" in a virtual machine which is installed Windows Server 2012 R2.

Device Manager 
1. On a virtual machine, log in as administrator.
2. Click "Start", enter "device manager".

3. Expand "Network adapters".
4. Right-click "Microsoft Hyper-V Network Adapter", select "Properties".

5. Select "Advanced" tab.
6. Select "Receive Side Scaling".
7. Next to "Value", select "Enabled".

8. Click "OK".

PowerShell
1. On a virtual machine, log in as administrator.
2. Launch "PowerShell" as administrator.
3. Perform "Set-NetAdapterRss -Name <NIC Name> -Enabled $True" to enable RSS on a network adapter.

Remark: Administrators also can assign how many virtual processors for virtual receive-side scaling (vRSS). For more information, please read Receive Side Scaling (RSS) in Windows Server 2012 and Windows Server 2012 R2.

To disable virtual receive-side scaling, administrators can perform "Set-NetAdapterRss -Name <NIC Name> -Enabled $False".

More information:

Virtual Receive-side Scaling in Windows Server 2012 R2

This posting is provided “AS IS” with no warranties, and confers no rights!