This article can also be found in the Premium Editorial Download "Storage magazine: The best storage for virtual desktops."
Download it now to read this article plus other related content.
Caching and SAN accelerators
Using a caching device or a SAN accelerator can make up for slower performing storage devices and provide more IOPS to deal with boot storms and other periodic I/O peaks. It can also save money because you may be able to use less-expensive storage devices but still be able to handle your VDI I/O workloads. Caching device like NetApp's Flash Cache can make a huge difference and can greatly increase the number of IOPS your storage is capable of. Configure your caching for the appropriate areas; events like boot storms generally are very read intensive so a larger read cache will make a big difference.
| Virtual machine RAM and paging | ||||||
Requires Free Membership to View
|
The amount of RAM assigned to a virtual machine can have a big impact on its performance. If you don't assign enough RAM, the operating system will start paging to disk, which can greatly increase the amount of disk I/O -- a situation you want to avoid as the needless storage I/O can degrade performance. Assigning too much RAM can cause swapping at the virtualization layer if a host has overcommitted memory, which can also degrade storage performance. It's OK to overcommit host memory and it's commonly done with virtual desktop infrastructure (VDI); just make sure you don't completely exhaust your host memory. |
||||||
SAN accelerators are a great way to add a high-performance caching layer in front of your existing storage device. FalconStor's Network Storage Server (NSS) SAN Accelerator for VMware View is an easy-to-deploy appliance that can improve a storage system's performance. It may even let you use low-cost SATA drives for your VDI storage and still get adequate performance.
This was first published in March 2011
Storage Management Strategies for the CIO

Join the conversationComment
Share
Comments
Results
Contribute to the conversation