Q&A: Virsto Software CEO Mark Davis discusses storage in the virtual world
Davis describes flaws with using the same physical storage techniques and virtualization problems such as VM I/O blender, VM storage bloat, and backup, cluster scalability
Follow @infoworldAs more and more people continue down the path of virtualizing their environments, one area that often gets overlooked in the process are the needs and the problems associated with storage. To find out more about this topic, I was able to speak with Mark Davis, CEO of Virsto Software, a company expecting to launch its first product by year's end. The company believes that storage is badly broken within the virtual world, and it plans on moving storage into the virtual age to keep pace with servers.
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InfoWorld Virtualization Report: At one level, virtual servers work just like physical servers. So a lot of people wonder, what's wrong with using the same storage techniques and technologies in the virtual world that we use with physical servers?
Virsto: The beauty of the hypervisor is that anything that worked on physical servers, in theory, will work on virtual servers. It's that promise, combined with the many benefits of virtualization, that makes virtualization so compelling, but saying that old tools designed for physical servers will work for virtual servers is not the same as saying they work optimally. As a VMware founder has been quoted as saying, "virtualization didn't break the applications, but it certainly broke the infrastructure."
Why did it get broken? Because the designers of infrastructure for physical servers made fundamental assumptions that are no longer true in the world of the hypervisor. This is abundantly true in the realm of data storage.
InfoWorld: Can you tell us, then, what are some of the fundamental assumptions about storage and storage management from the physical world that are false for virtual servers?
Virsto: One that is well known is the assumption that the server has plenty of headroom. Backup is a CPU and I/O hog, and that was OK when we were running servers at 7 percent utilization. Now we've consolidated servers and no longer have that headroom, so firing up a backup job can really slow down the app being backed up. But the problem is pernicious, because all the other VMs on the physical server are also impacted. Completely unacceptable, and this isn't the only place where the assumption of unshared resources bites us.
