While I enjoyed a holiday and was drinking my piña colada cocktail at a sunny beach in the south of France, my virtualization friend Duncan Epping over at Yellow-Bricks.com has snagged away a real cool scoop regarding the release of a new technical paper about VMware vSphere 4.1 Network performance ;-) As Duncan points out is his article it’s real interesting to know that a single virtual machine actually can saturate the bandwidth of a 10Gbps physical network card. In fact this newly released performance study will show that with using regular TCP/IP sockets, virtual machines on the same host can communicate at rates of 27Bbps. This is a 10 times increase in throughput from ESX 3.5. Even a single virtual machine with multiple virtual NICs running on vSphere can easily saturate the bandwidth of four 10Gbps NICs for a cumulative throughput of more than 35Gbps.
http://www.vmware.com/resources/techresources/10181
This paper demonstrates that vSphere 4.1 is capable of meeting the performance demands of today's throughput-intensive networking applications. The paper presents the results of experiments that used standard benchmarks to measure the networking performance of different operating systems in various configurations. These experiments examine the performance of VMs by looking at VMs that are communicating with external hosts and are communicating among each other, demonstrate how varying the number of vCPUs and vNICs per VM influences performance, and show how the scalability results of overcommitting the number of physical cores on a system by adding four 1-vCPU VMs for every core.
