Earlier this week, Communications News published our most recent piece on the impact of server virtualization, Virtualization: Overcoming the Input/Output Pitfalls
This is not the first time we've outlined this situation. Gear6 continues to see many scenarios where customers are anxious to deploy server virtualization but have not always considered the I/O implications.
Some of our previous blog posts include:
This situation is slowly but surely becoming well-recognized in the industry:
“Customers find that when they implement server virtualization but use the same storage, all of a sudden that storage becomes a huge bottleneck,” Taneja says. [source here]
While administrators often focus on CPU and memory constraints, storage-related performance is also a common bottleneck in a virtualized environment. -Anil Desai [source here]
Virtualization tends to place heavy demands on the storage I/O subsystem. With multiple OSs running concurrently, each with its own page file and application, I/O traffic increases substantially. Disk resources are under greater and greater contention. The I/O subsystem quickly becomes the primary bottleneck to system performance. [source here]
Another major component and perhaps less acknowledged is the disk subsystem. In many cases, depending the purpose and application of the guest/virtual systems, the disk bottleneck will be the most significant barrier to performance. [source here]
No question there is something under the covers here. It may be too early to tell exactly how virtualization growth pans out, and what bottlenecks get exposed, but a renewed focus on storage and storage performance is likely to be a big part of the equation.