at Citrix. He was one of the founders of XenSource and was on the faculty of Cambridge University, where he earned his Ph.D. in computer science. Crosby grew up in South Africa and has master degrees in applied probability and computer science.

Gustav. This is a pseudonym due to the policies of his employer, a large financial services company where he runs distributed systems. Early in his career, Gustav wrote assembler code for telephone switches and did CAD/ CAM work on the NASA space station Freedom. He later moved to large system design while working on a government contract and subsequently worked for a messaging and security

alization, virtualization management, and application virtualization. Stewart is a Microsoft Certified Architect and is on the Board of Directors of the Microsoft Certified Architect Program.

Steve Herrod is the CTO of VMware, where he’s worked for seven years. Before VMware, Herrod worked in Texas for companies such as EDS and Bell Northern Research. Earlier in his career Herrod studied with Mendel Rosenblum, the founder of VMware, at Stanford and then worked for Trans-Meta, a computer hardware and software emulation company.

Steve Bourne is chair of the ACM Professions Board. He is also a past president of the ACM and Editor-in-

simon cRosBY: The power-savings issue is a big red herring because the CPU is a small portion of the total power consumption compared to spinning all those disk drives in a storage array. I’ll be the first one to say that free, ubiquitous CPU virtualization is just an emergent property of Moore’s Law, just part of the box. Memory is another major power consumer and memory architectures are definitely not keeping up. When you’re talking about virtualizing infrastructure, you should be talking about what bits of it you virtualize and how: CPU, storage, and/or memory. You have to look at the whole thing. As for showing lower overall power consumption, I have yet

steve Bourne

startup company in Silicon Valley, taking it public in the mid-1990s. After starting his own consulting firm, he began working at his first large financial firm. Seven or eight years later, he landed at his current company.

Allen Stewart is a Principle Program Manager Lead in the Window Server Division at Microsoft. He began his career working on Unix and Windows operating systems as a system programmer and then moved on to IBM, where he worked on Windows systems integration on Wall Street. After IBM, Stewart joined Microsoft, where for the first six years he worked as an architect in the newly formed Financial Services Group. He then moved into the Windows Server Division Engineering organization to work on Windows Server releases. His primary focus is virtualization technologies: hardware virtu-

mache creeger

 

Chief of the ACM Queue editorial advisory board. A fellow alumnus with Simon Crosby, Bourne received his Ph.D. from Trinity College, Cambridge. Bourne held management roles at Cisco, Sun, DEC, and SGI and currently is CTO at El Dorado Ventures, where he advises the firm on their technology investments.

 

mache cReeGeR: Virtualization is a technology that everyone is talking about, and with the increased cost of energy the server consolidation part of the value proposition has become even more compelling. Let’s take that as a given and go beyond that. How do we manage large numbers of virtualized servers and create an integral IT architecture that’s extensible, scalable, and meets all the criteria that reasonable people can agree on?

allen stewart

 

to see a good calculation for that.

GustaV: I support virtualization for a number of reasons, but cost savings isn’t one of them. What I typically see is that the server guy makes a decision to reduce his costs, but that significantly impacts storage and the network, making their costs go up.

To put eight software services on a single machine, instead of buying the $3,000 two-socket 4GB 1U blade, I bought the four-socket, 16GB system for $20,000. While that calculation provides an obvious savings, because I want to use VMotion I have to purchase an additional storage array that can connect to two servers. The result is that I paid more money than the traditional architecture would cost to support the same service set.

That’s why you see a large interest in virtualization deployment followed