Mendel Rosenblum, VMware founder, headlined Wednesday’s keynote focusing on the future of virtualization technology.
Some highlights:
- Virtualization allows you to view the hardware in your data center as pools of resources. You map applications onto resources dynamically to optimize how your computing hardware is used. Customers benefit by buying less hardware, using less power, and just adding more memory, disk, and cpu to the pool when needed.
- The virtualization layer export four primitive functions: Multiplexing, so you can run multiple virtual machines on the same hardware; Suspend, so you can put a virtual machine into storage; Resume (provision), potentially on a different box; and Migration, so you can move running virtual machines between physical boxes (VMotion).
- The audience favorite: The virtualization layer enables you to record all execution steps from a virtual machine and then replay them on another machine. VMware records them in a very compact way, so that you can track all changes in your environment. This means you can now reproduce non-reproducible bugs by replaying the steps that led up to a crash.
- VMware is working with hardware vendors to reduce the overhead in mapping virtual hardware to physical hardware. VMware is also simplifying the virtualization layer to increase robustness and make the virtualization layer small enough to trust. This is key for security and reliability — and even innovation. You’re limited by the complexity of the system you build — by building smaller and less complex, it’s easier to innovate.
- Multi-core is very exciting for virtualization. On multi-core, there is less overhead for VMotion because the processors are "closer" to each other.
- Memory virtualization: With page sharing, you can configure the sum of all memory in all VMs to be greater than the total memory on the hardware. Shadow page tables store a copy of the page table in the virtualization layer. AMD nested page tables; Intel extended page tables do this mapping in hardware for better performance.
- Another interesting area of research is pass-through i/o devices. You get speed with pass-through, but you lose ability to do format conversion (e.g. scsi to SAN), fault tolerance if a link fails, VMotion, resource mgmt (traffic shaping), security policy enforcement, etc. The goal is to get acceleration of pass-through without losing this additional functionality: i/o devices smart enough to export multiple personalities – each one passed through the virtualization layer to a different vm.
- Traditional view of OS is to drive the hardware and support abstractions for applications, like files and processes. The industry has come to view the operating system as an extension of the hardware. You think of the system as the operating system.
- Goal of OS is to support as many application environments as possible. "People ask me what’s the best OS? The best OS is the one that supports the applications you need." The problem is that the OS became too complex because it needed to have features to support a huge variety of applications. Most telling is that it’s hard to innovate the OS because it’s so complex — millions of lines of code. VMware can innovate because we keep the VMM layer simple.
- So, what’s happening to the OS? You don’t need hardware management pieces because that’s handled by the virtualization layer. You also don’t need features to support all apps, just the features that support your app. And then you bundle it into the VA. So the OS becomes much smaller.
- An example: BEA Java VM. Currently, it must run on different environments,e.g. Windows, Linux, Solaris. With a virtual appliance, you just build it once as a VA with a highly tuned OS. Another example is a firewall, where you can build Checkpoint and the OS in a virtual appliance. Or you can do the same thing with a CRM, including an app server, crm software, and database as a VA. Looking at the Checkpoint VA, you can run it on the Macintosh
- Virtual Man told the audience that there are only 18,324 possible VMware products — because that’s how many combinations of three letter or four letter acronyms starting with the letter V: VMTN, VMDK, VMI, etc.
But the most interesting factoid from today: 300 people showed up for a lab at 6:30 this morning!
See you all at VMworld 2007, September 11 – 13 in San Francisco.
