In the second part of my Catalyst server virtualization coverage wrap-up, I reflect on three sessions:

• Mark Russinovich – New Trends in Application and OS Development for Virtual Environments
• Simon Crosby and Scott Drummond – The Thrilla in California
• Richard Jones and Chris Wolf – Hypervisor Competitive Differences

Mark Russinovich (Technical Fellow, Microsoft)

Mark Russinovich spoke about the importance for developers to understand the nuances of virtualization and to write code capable of taking advantage of virtualization’s dynamic resource management capabilities. He specifically made the following recommendations:

• Applications must be able to adapt
  • Avoid relying on hypervisor services that expose underlying physical hardware or topology
  • Use operating system notification services to monitor changes to I/O, memory and CPUs
  • Separate state to enable composition scenarios
• Operating systems must adapt
  • Leverage hypervisor services to enable dynamic resource assignment
  • Enable virtual disk as both physical and virtual image format
• Management tools must adapt
  • Include system load balancing, migration, and dynamic resource allocation policies

I’ve been pressing clients for months to use RFPs to press software vendors on how their applications support dynamic resource add (without a restart, of course). I asked Mark about Microsoft offering a best practices guide for developers on MSDN, and he said this was something they would look into. MSDN already has good information on Large Page Support, a feature that when leveraged by the application, can significantly improve memory performance on platforms that support Intel EPT or AMD RVI.

The Thrilla in California (Simon Crosby – Citrix, and Scott Drummonds – VMware)

Many at the conference called this debate their personal conference highlight, and you can view it online if you missed it. There were plenty of sound bites in the debate, including this one by Scott Drummonds -

“You guys aren’t even benchmarking your own product. Why are you going to benchmark ours?”

When talking about Project Virtual Reality Check’s benchmark results and VMware’s benchmark requirements, Simon noted -

“That methodology that Scott has espoused basically prohibits the notion of the legitimacy of that result.”

I have watched the replay three times and still have a hard time declaring a winner. I liked the factual data presented by Scott and his advice on leveraging industry standard benchmarks to assess workloads for applications such as Exchange, Oracle, Apache, and SQL Server. However, a couple of attendees commented that they were surprised that Scott would compare VMware to Oracle when defending VMware’s EULA restrictions on public benchmarking. Many attendees voiced displeasure over Oracle licensing and support for virtual environments while at the conference. Simon’s point that user experience is what matters most is also true, but you need quantitative methods to measure something that can be very subjective. That’s why I have been a fan of Project VRC. I’d like to see VMware address their issues with Project VRC so that we’ll have at least one independent standard we can use (albeit for virtual desktop and terminal services workloads) before the SPEC Virtualization benchmark is released. VMware has done a very good job showing performance results of enterprise apps (e.g., Exchange and Oracle) on VMware infrastructure, while providing a community to share best practices. I’d like to see something similar from the folks at Citrix.

There was considerable coverage of the debate in the blogosphere, and you can read additional perspectives in these posts:

• Drummonds vs. Crosby on Virtualization Performance
• The Thrilla in California: Citrix Dukes it out with VMware over Virtualization Performance and VMware’s EULA
• VMware/Citrix Hypervisor Performance Ding Dong
• Citrix and VMware Debate Hypervisor Performance at Catalyst – VIDEO
• FIGHT: VMware vs Citrix
• VMware vs Citrix @ Burton Group Catalyst event
• Hypervisor Performance Debate – VMware versus Citrix
• Debate between Simon Crosby (Citrix) and Scott Drummonds (VMware)
• Drummonds vs Crosby

Hypervisor Competitive Differences (Richard Jones and Chris Wolf)

Richard and I wrapped up the day with a talk about hypervisor competitive differences. We received some great feedback following the debate and are incorporating it into our upcoming competitive differences presentation at VMworld North America. Attendees were most interested in hearing about competitive differences between VMware, Citrix, and Microsoft server virtualization platforms. VMware and Citrix offer solutions that meet 100% of our requirements, and at VMworld we’ll be going deep on the small differences that exist between features that may appear similar on the surface. If you’ll be at VMworld in a few weeks, I recommend signing up for session TA2400, which is Tuesday September 1st at 4:00.

Thanks to all of the attendees for sharing your insights throughout the week. The next Catalyst conference will be in Prague in April 2010. Strong client participation helped make Catalyst North America a huge success. If you have suggestions for Prague or future conferences, please let us know.