Mavericks added memory compression, a way to maximize physically installed RAM that gave new life to my MacBook Air. During the slow post-restart, pre-usable phase, neither memory nor disk storage was an issue. Using Activity Monitor, and in the Terminal, the top command, I could see I was often running up against the limits of physical memory, but the Mac didn’t seem to be under “memory pressure,” which would cause a lot of disk activity. That helped, but didn’t fix the problem all the way. WhatSize let me quickly locate and delete 90GB of files I didn’t need. There was clearly something to do with temporary files and available disk storage slowing things down. I used WhatSize (which I also reviewed) to free up almost 90GB in unneeded files, which seems to help a little.
