A company implementing virtual machine technology can expect to reap great rewards. Where before a new server installed would have meant a new physical machine (at the least a rack mount)—along with the power to run it and the space to house it—a server can now be fully deployed and run on an existing hardware platform. It will have everything the physical server would have had, including its own instance of an operating system, applications and tools, but no footprint and a tiny fraction of the once-required power.
In addition to the footprint savings, virtual machines also bring speed to the table. It can be deployed and up and running in minutes instead of hours. It allows users to deploy their own machines—something unheard of in the past. It means a great time savings for users and IT personnel alike.
Virtual technology is now being used for many purposes. For example, it brings a great boost to Storage Area Network (SAN) technology which, in itself, takes an enormous amount of stress off of a system by moving storage traffic off the main production network.
Without proper optimization, however, virtual technology cannot bring the full benefits on which an enterprise depends. A major reason is that virtual technology—along with SAN and other recent innovations—relies, in the end, on the physical hard drive. The drive itself suffers from file fragmentation, which is the state of files and free space being scattered in pieces (fragments) all over the drive. Fragmentation causes severe I/O bottlenecks in virtual systems, due to accelerated fragmentation across multiple platforms.
Virtualization suffers from other issues that are also the result of not being optimized. Virtual machine competition for shared I/O resources is not effectively prioritized across the platform, and virtual disks set to dynamically grow do not resize when data is deleted; instead, free space is wasted.
It is vital that any company implementing virtual technology—and any technology in which it is put to use, such as SAN—employ an underlying solution for optimizing virtual machines. Such a solution optimizes the entire virtual platform, operating invisibly with zero system resource conflicts, so that most fragmentation is prevented from occurring at all. The overall effect is that
unnecessary I/Os passed from the OS to the disk subsystem are minimized, and data is aligned on the drives for previously unattainable levels of speed and reliability.
Additionally, a tool is provided so that space is recovered on virtual disks that have been set to grow dynamically.
Such a virtualization optimization solution should be the foundation of any virtual machine scheme for all enterprises.