Intel 7400 VMM overhead Switching load Interrupt bottleneck, 2x throughput Near Native 10 GbE

White Paper Consolidation of a Performance-Sensitive Application

VM	1		VM	VM	n
		2
Virtual			Virtual	Virtual

VMware with NetQueue

NIC with

VMDq

LAN

Figure 5.. Network data flow for virtualization with VMDq and NetQueue..

10.0

9.29.5

8.0

(GB)	6.0
Throughput		Jumbo Frames
	4.0
		Without VMDq

With VMDq

4.0 With VMDq

2.0

•2x throughput

•Near Native 10 GbE

Figure 6.. Tests measure wire speed Receive (Rx) side performance with VMDq on Intel® 82598 10 Gigabit Ethernet Controllers..

VMM overhead

•Switching load

•Interrupt bottleneck

We can optimize the network I/O solution to solve both of the issues above.

In Figure 5, we show the effect of using the new Intel® VMDq hardware in our latest NICs along with the new VMware NetQueue software in ESX 3.5. In this case, the network flows destined for each of the VMs are switched in hardware on the NIC itself and put into separate hardware queues. This greatly simplifies the work that the virtualization software layer has to do to forward packets to the destination VMs and delivers improved CPU headroom for application VMs. Each of the queues noted above is equipped with a dedicated interrupt signal that

can be directly routed to the destination VM for handling. This allows us to spread the load of a 10 G pipe across the processor cores running those VMs. In this way we can break through the single-core interrupt processing bottleneck to deliver near line- rate performance even at 10 GbE speeds.

In Figure 6, we can see that the receive performance with VMDq + NetQueue is 9.2 Gbps with standard 1518-byte packet size and 9.5 Gbps with jumbo frames. This is more than double the throughput without these new technologies enabled and very close to maximum theoretical line rate.

VMDq and NetQueue

•Optimize switching

•Load-balance interrupts

6