Speeding up VMs with Flash Read Cache

Flash Read Cache is a new feature introduced in vSphere 5.5 which allows accelerating virtual machines by using flash memory installed on the host. In most cases, this will be achieved using SSD disks installed on the hosts. PCI-E devices can also be utilized.

This feature, which is completely transparent for a virtual machine, can increase the read speed. It can also improve the write speed by reducing storage read operations. As a result, it not only accelerates busy virtual machines but also reduces storage I/O load by generating less storage network traffic.

With Flash Read Cache systems, applications considered before to be too I/O intensive can now be virtualized.

Flash Read Cache also supports vMotion, so virtual machines with virtual drives configured to use this feature can be migrated between hosts that are configured with flash resource. There are two settings available for cached content migration: always migrate (copy) and never migrate (drop...