Whitepaper: Performance Evaluation of AMD RVI Hardware Assist

I recently discussed the effect of RVI/Virtualized MMU on Transparent page Sharing, and just 5 days later VMware published this extensive PDF:”Performance Evaluation of AMD RVI Hardware Assist“.

AMD recently introduced its second generation of hardware support for virtualization, incorporating MMU virtualization called Rapid Virtualization Indexing (RVI). Hardware support for MMU virtualization can improve performance, particularly for MMU-intensive workloads.

VMware ESX 3.5 leverages this RVI support in AMD processors. This paper compares the performance with and without RVI of a number of industry-standard benchmarks and microbenchmarks running in VMware ESX 3.5, Update 2 on AMD Opteron 8384 (”Shanghai”) processors.

Read the PDF for more indepth info, but I think the most important bit is:”The improvement provided by RVI increases with larger numbers of vCPUs; in the four vCPU case RVI performed 42% better than BT.” And that’s just for one of the benchmarks. If you’ve got an AMD processor or Intel Processor that supports virtualized MMU, be sure to do a benchmark and it probably will be beneficial to turn it on.

http://www.yellow-bricks.com/2009/03/17/whitepaper-performance-evaluation-of-amd-rvi-hardware-assist/