We just bought a new array with a feature called FlashDisk SSD Read Caching.
the vendors implementation of this technology is this: It basically caches all frequently read blocks requests which are 16KB or smaller in controller dedicated SSD, up to 1.6TB per controller.
We are concerned that we paid all this extra money for SSD read cache and wondering if it will ever come into play because VMFS5 filesystem uses 1MB block size.
WE have Oracle DB currently set to use 8KB blocksize. Now if VMFS collects the Oracle 8KB requests and puts them into 1MB blocks, then Im I correct to believe the SSD read cache pool will never be used? is there a way to allow the Oracle 8KB blocks to get to leverage the SSD read cache using vmfs5 file system? or is RDM needed here?
Thanks!