My Customer is looking to enable Image-volume caching feature. This is especially relevant to their environement as they only use boot from volume virtual machines

However, after their discussions and validation with DELL, DELL PowerFlex has some usage limitations as reported by c42:  have one limitation with PowerFlex, as a single volume topology that includes all snapshots and clones cannot exceed the number of 126. If we do not limit it at 20/35/40, at some point backups will not be able to run, and customers will not be able to create snapshots
 
More details on the topic in the thread, in rhos-storage, with object Volume caching with Glance and Cinder