This topic is about Microsoft Virtual Machine Queue (VMQ) in Hyper-V R2 ServicePack 1.
In this Microsoft Architecture design of Virtual Machine Queue you can see the difference between VMQ in Microsoft Hyper-V 2008 and Hyper-V 2008 R2.
Improved Virtual Networking Performance
The new Hyper-V leverages several new networking technologies contained in Windows Server 2008 R2 to improve overall VM networking performance. Two key examples are support for Jumbo Frames and new support for the Virtual Machine
Queue (VMQ). Support for Jumbo Frames was also introduced with Windows Server 2008. Hyper-V in Windows Server 2008 R2 simply extends this capability to VMs. So just like in physical network scenarios, Jumbo Frames add the same basic performance enhancements to virtual networking. That includes up to 6 times larger payloads per packet, which improves not only overall throughput but also reduces CPU utilization for large file transfers.
VMQ allows the host‘s network interface card (NIC) to DMA packets directly into individual VM memory stacks. Each VM device buffer is assigned a VMQ, which avoids needless packet copies and route lookups in the virtual switch. Essentially, VMQ allows the host‘s single NIC card to appear as multiple NICs to the VMs, allowing each VM its own dedicated NIC. The result is
less data in the host‘s buffers and an overall performance improvement to I/O operations.
Here is an example of the propeties of a NIC Driver.
Microsoft VMQ is important to get the best performance in your virtual network.
More information about Microsoft VMQ is here :
MSDN site
Enabling Virtual Machine Queue on the Management Operating System
Posted by James van den Berg 
