Only read performance is improved by HP MSA's internal caching and tiering features.1 In comparison, VirtuCache improves the performance of reads and writes for MSA, and it does so by caching to in-VMware host SSD or RAM. There are other differences as well.
CEPH is a popular open source storage software. However its write latencies are high. VirtuCache caches CEPH volumes to in-host SSDs and by doing so reduces VM level latencies considerably.
Fairbanks Sewer and Water (FSW) wanted to improve the performance of their server VMs (especially their server VMs running SCADA) and Horizon View virtual desktop VMs. Their virtual desktop VMs were exhibiting all the classic symptoms of storage related issues – cursor freezes, long boot times, long VM provisioning times, jittery audio/video.
By not using dedupe, compression, or RAID, using slow HDDs in centralized storage, and moving SSDs to compute hosts, we arrived at low price per capacity and performance for video storage.
Here are unique requirements of video storage, some are obvious and others not so much, that inspired us to put together a different architecture than the conventional storage OEM design.
VirtuCache is installed in VMware vSphere kernel. It then automatically caches frequently and recently used data from any backend storage to any high speed media (RAM/SSD) in the VMware host. By bringing large amounts of 'hot' data closer to the VMware host GPU and CPU, VirtuCache improves the performance of all applications running within VMs including GPU assisted operations.
Dell's PowerEdge VRTX hyper-converged appliance can either have all hard drive datastores or all SSD datastores, but you can't have SSDs act as tiering or caching media for VRTX volumes. That's where VirtuCache comes in.