My 2011 i7 MBP was running like crap doing pretty menial tasks. 480gb SSD with plenty of space, 16gb of RAM. It was also running very hot far too often despite cleaning the fans. There was no reason for it and it was really starting to bug me. Filevault was on, so out of curiosity I turned it off to see if it'd help and voila...this thing runs as well as it did out of the box when I brought it home 7 years ago. I've seen some threads with people asking about the effects of FileVault on performance, and the general consensus was that if you have a SSD, you shouldn't really see a drop in performance. I've found this not to be the case so I wanted to pass this along just in case anyone was looking to get a bit more speed from their aging machine.