I have a late 2013 model 21.5" iMac with 16GB ram running OS X 10.11.4. I'm having this problem that it is consistently allocating up to/close to 32GB of swap. There are not many swap-outs, so I guess this is not having much impact on performance, but it seems like all applications are just allocating memory out of control. This is also causing 32GB of my 250GB SSD to be occupied by some ******** that is never used and I've been getting low disk space warnings. I have not experienced this with my MacBook Pro or previous Macs I had. In order to try to remedy the problem (and another one which I'll describe at the end of the post) I set up OS X on a new SSD and did not do any migration from the old drive, but now the problem is back again. Looking at Activity Monitor, here are some values from the "Memory" column: Photoshop CC: 4.03GB (no file open) Dropbox: 4.00GB Skype: 3.73GB Finder: 3.67GB (single window open) Notification Center: 3.57GB Dock: 2.97GB Google Chrome: 2.95GB CrashPlan menu bar: 2.56GB loginwindow: 2.51GB Lightroom: 2.51GB iTerm: 2.50GB (single terminal open) Flux: 1.31GB I find it especially strange that Notification Center, Dock and loginwindow are allocating so much memory. If anyone has some suggestions, explanations or remedies for this problem, they would be greatly appreciated. *the other problem I was having was that Adobe Photoshop was always using at least one full CPU core, even when it had no file open.