VMware announced the deprecation of vFlash Read Cache (vFRC) in the release notes of vSphere 6.7 Update 2. vFRC continues to be supported for vSphere 6.0/6.5/6.7.
However, the next major release will not. https://blogs.vmware.com/vsphere/2019/04/vflash-read-cache-deprecation-announced.html
vFRC is a Hypervisor-based caching solution feature introduced with vSphere 5.5.
It pools multiple flash devices as a resource and is part of the vSphere and vSOM Enterprise Plus license.
The goal of vFRC feature is to enhance performance of certain I/O workloads that exhibit characteristics suitable for caching by using local flash media to create a cache repository for read I/Os.
https://storagehub.vmware.com/t/vsphere-7-core-storage/eoa/
Because vFRC currently has a minimal customer base and because VAIO is a better way to implement caching (and it allows 3rd party vendors to create custom caching solutions) the solution is now deprecaed.
When you upgrade to vSphere 7, you will receive a warning message that vFRC will no longer be available. “vFRC will be gone with this upgrade, please disable vFRC on a VM if using it.”
But if you look at the menu of vSphere 7.0 you will still see some option. Why?
Basically because the vFRC framework was sharing part of the UI and the architecture with the swap to SSD feature and this second feature is still present in vSphere 7.0.
