Second, virtual servers have unique I/O performance characteristics. One big problem is the "VM I/O blender," in which disk I/O performance drops precipitously as VMs are added to a box and I/O-intensive applications are virtualized.
Third, virtual server storage management is more complex than for physical servers. Currently, it takes too much administrative time and is fraught with opportunities for mistakes. Storage management is integral with VM management, so the hypervisor needs a certain amount of integrated storage management.
Finally, a consistent complaint is the total cost of VM storage. Organizations go virtual to save money, but often, all the money saved on servers gets spent on extra storage, which is crazy.
InfoWorld: What are some of the challenges that Virsto is aiming to solve for Microsoft Hyper-V customers?
Davis: Our goal is to make virtual storage as empowering as virtual servers. That means making it easy to optimally provision VM storage without leaving the Hyper-V Manager console, enabling simpler backup, dramatically reducing the amount of disk space consumed by VM images, and improving the storage I/O throughput of Hyper-V servers. And we aim to do this with a small, simple piece of software that has no guest VM footprint and works with any storage hardware.
InfoWorld: What are some of the options we have had for solving these challenges?
Davis: Two choices. First, be less aggressive in adopting virtualization. That is, leave more applications on physical servers, and accept reduced consolidation benefits by running fewer VMs per box.
The second option is to overprovision storage. Buy more terabytes, spindles, I/O hardware, higher-end storage arrays, cache, and expensive software licenses. Ironically, virtualization helps us not overprovision servers, yet to achieve it we have to overprovision storage!
InfoWorld: Why start with Microsoft Hyper-V? Why not launch with VMware since it has the majority of the market?
Davis: Microsoft Windows Server 2008 Hyper-V R2 is rapidly gaining adoption. There are several compelling aspects to Hyper-V, yet there are opportunities for Microsoft partners like Virsto Software to add significant capability. The Microsoft platform is relatively easy to integrate with, Microsoft's organization has been a pleasure to work with, and customers adopting Hyper-V are looking for simple, low-cost storage solutions that unleash the full power of virtualization. That made it easy to choose Hyper-V as our launch platform.