I get this question from time to time, “How does Flex-IO compare to VMware’s View Storage Accelerator (formerly known as Content Based Read Cache)?” The answer is not one or the other it’s you should use both!

Let me explain why:

VMware View Storage Accelerator is a “Read Cache” only so it does not help with writes, it’s also limited to 2 GB of host memory. However, it does cross all images for finding common blocks to serve from RAM vs going to disk so this works well with Flex-IO.

When you combine View Storage Accelerator there are a few benefits.

  1. Flex-IO does not cross replica’s for common read blocks, Flex-IO common read blocks only relate to the replica and link’d clone. So, if you’re pushing out more than one pool on top of Flex-IO, View Storage Accelerator can help optimize read access replica’s taking some of the stress off Flex-IO and reducing Flex-IO CPU. From a RAM point of view removing some of the reads from Flex-IO gives more room for handling writes in the same RAM foot print, which never hurts.
  2. Refresh times,  login times, application load times all do better with View Storage Accelerator, but when the 2 GB runs out you’re back to the speed of your disk again, this is where Flex-IO can follow up and help. Flex-IO does not have any kind of CAP for how much RAM you want to give it for Read and Write Caching.
  3. As I stated above, its “Read Cache” NOT Write Cache, so adding Flex-IO is going to help speed up writes as well where View Storage Accelerator by its self does not.

Side note: You can enable Content Based Read Cache at the host level and use it with any VDI platform, XenDesktop, vWorkspace, etc.

I hope this helps to understand that you should be using Flex-IO and View Storage Accelerator together.

For more information on Liquidware Labs Flex-IO visit the Flex-IO Product Page or contact sales at Liquidware Labs.