An article posted on the KVM blog confirms that KVM developers have achieved native network I/O performance using PCI passthrough with Intel’s VT-d technology. It means that one of the two bottlenecks (network and disk) in system virtualization is going to be eased soon, if not completely removed, resulting in a faster adoption of system virtualization technologies. A quote from the development mailing list follows:
Ben-Ami Yassour wrote:
In last few tests that we made with PCI-passthrough and VT-d using iperf, we were able to get the same throughput as on native OS with a 1G NIC
After some minor tweaking these patches will be rolled out.