Building Block Architecture for Superior Performance

by Scott Drummonds at VMWare

If any of you have heard me speak in the numerous events I've done in the past two years, you may have heard me detail the areas where virtualization performance can exceed native. There are scalability limitations in traditional software that make nearly every enterprise application fall short of utilizing the cores that are available to them today. As the core explosion continues, this under-utilization of processors will worsen.

In 2008, I visited VMworld Europe and showed on using multiple virtual machines on a single physical host could circumvent the limitations in today's software. In that experiment we showed that 16,000 Exchange mailboxes could be fit on a single physical server when no one had ever put more than 8,000 on in a single native instance. We called this approach designing by "building blocks" and were confident that as the core count continued to increase, we'd continue to expose more applications whose performance could be improved through virtualization.

On Thursday last week SPEC accepted VMware's submission of a SPECweb2005 result. And last night we posted an article on VROOM! detailing the experiment and providing information on the submission. This submission is an incredible first for us: not only have we shown that we can circumvent limitations in web servers, but we posted a world record performance number in the process. Of course, if any of you have seen Sreekanth Setty's presentation at VMworld on his ongoing work on SPECweb2005, this result wouldn't surprise you:Getting a benchmark standardization body like SPEC to approve these results isn't always easy. Most of the industry remains stuck in a mode of thinking of performance as a single instance's maximum throughput.

But given the scale-out capabilities of a large number of enterprise applications I'd argue that benchmarking should account for scale-out capabilities on a single box. VMware's customers follow this practice faithfully in sizing their deployments to match their needs and everyone wants to know the platform's ability to handle this use-case. SPEC's willingness to accept results showing building blocks on a single host is commendable and progressive. As more benchmarks approve submissions like these VMware will continue to be able to show record numbers.