I've done some extensive testing on another server.
I was unable to reproduce the performance difference.
It took me a while, but eventually I realized that the difference between the test server and the production server is that the production server was using BitLocker
I created a volume without enabling BitLocker and performance was as expected when not added to a cache task.
I don't know if this relates to OPs use case, but I certainly retract my previous statements about performance issues relating to PrimoCache. Sorry
![Embarrassed :oops:](./images/smilies/icon_redface.gif)