When I purchased my 5N, I made sure to max out the mSATA cache, using a Drobo recommended card. My 5N seems just as slow as my FS. Am I missing something? Or did I just waste a lot of extra money?
mSATA is only a READ cache for hot data (frequently accessed small files such as thumbnail images).
It will not help with write operations or large files. READ cache is built over time as the system gathers statistics about what to put on mSATA disk.
So if your usage pattern doesn’t fit these criteria, then you might as well take out that mSATA disk and use it somewhere else where it would be more effective.
when you say maxed out - what do you mean?
you wont see any additional advantage from cards over 64GB