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Comment by yapcguy | Hacker News Reader

Does anyone know if the memory swap issues[1], which plague Lion and Mountain Lion, have been fixed?

[1] You could have 20GB of hard disk space free, but use XCode, Firefox and a few other apps, and soon you're down to 10MB and you get the dreaded "Your Mac is running out of disk space" dialog and you have to force quit all your apps, and type "purge" into a Terminal in a desperate attempt to get the swap released...

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I'm at 53 MB used of 1 GB total swap after three days of uptime, while on 10.8 I would go far over that within minutes of startup (usually topping out at ~10 GB total after a day or two), so something does appear to have changed.

I run several virtual machines on my 8 GB MBP and I have never seen swap issues. Are you sure your problems are actually caused by swap?

"purge" doesn't touch swap, it discards disk cache. Its use (according to the man page) is to simulate cold boot disk performance. The command has no use for memory management, because disk cache is automatically discarded when free memory runs out.

Fairly sure, I've been suffering with this on 10.7 and 10.8 on different machines. Some more info here:

http://workstuff.tumblr.com/post/20464780085/something-is-de...

I second this. It's a big enough issue for me that if Mavericks doesn't fix it, I'll be switching back to Linux.

On my previous '09 MBP with a 5400rpm drive disabling the pager meant it went from a really slow crappy experience to amazingly fast. I had periodic hangs when I used too much memory, but I would put up with those to have general performance not suck.

I eventually bought a 2012 Air (got sick of carting a 17" laptop around) and so haven't seen any issues (yay for ssd!).

Looking forward to seeing if this is fixed - I've always found page management decisions made by OSX to be less awesome than linux.

This sounds more like an issue with an app (or a kext) consuming way too much memory than any innate OS-level issue with paging. Activity Monitor and/or top can be useful in figuring out what the heck is using up all that memory. Xcode can use a really surprising amount of memory sometimes but it's not going to just gobble up 20GB of pageable VM.

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