Has anybody else noticed that their Mac is using a ton of Virtual Memory?

I have 2gb of RAM and my Mac is using 41gb of VM. Is there anyway to dump the VM file and start a new one?
Just seems like my system is using a TON of hard drive space for a VM!

11/29/2007 9:53:12 AM

if you're looking at it in activity monitor, from what i remember that's just how much space the programs could be using, but doesn't mean that's how much they are using.. if that makes sense. (in other words, large amounts are normal)

note: my VM size is 33 gigs.. (with 2 gigs of RAM)

[Edited on November 29, 2007 at 11:10 AM. Reason : .]

11/29/2007 11:06:27 AM

most of the time mac's aren't even using VM... (it's weird)

11/29/2007 11:29:04 AM

that does sound excessive (even though i have no benchmark to base that statement off of), but it seems like a case of "if that space isn't being used anyway, it's not hurting anything".
of course, i can't imagine that paging from a 40GB VM file/structure would be any faster than scanning the disk normally.....

11/29/2007 11:32:05 AM

true

11/29/2007 12:52:03 PM

Yeah, I opened up Activity Monitor to try and see.

My VM is around 45gb now, which might explain where all my 148gb of hard drive might have gone to.

Either way, things aren't really adding up to the amounts they should.

11/29/2007 12:59:36 PM

Can't you go to the activity monitor and see what app is eating up that?

11/29/2007 1:20:45 PM

does the VM actually take away from the shown free drive space?
I've done some DiskInventory runs on my Mac, and as I recall, it actually did show a 2-3GB file dedicated to VM, and it was counted as "space used". i've never seen mine go anywhere near the size of yours though

11/29/2007 1:23:09 PM

OS X is not actually using all of those 45GB independently.

I think the way it works is that each running process is kind of run in its own memory bubble, and each process "thinks" it has 2GB (or however big the VM page file is) to run in all on its own, when really, it's just using what its using. And when OS X reports what the VM usage is, it's counting up all those "virtual" bubbles separately. The only reason I would imagine that its doing this is because it makes the accounting process, if an app actually needs paging out, a little quicker and easier.

Of course, this is all just my presumptions based on using OS X and see what it does from the front end.

Look in activity monitor, fan all the processes out, and look at the virtual memory/process... notice a pattern? There's no way each one of those processes is using 500MB a piece. It must be just the way OS X accounts for memory map of individual processes.

[Edited on November 29, 2007 at 1:57 PM. Reason : ]

11/29/2007 1:55:52 PM

^ yea that's exactly how it works.

11/29/2007 4:59:46 PM

^^
yep. more snippets here:
http://discussions.apple.com/thread.jspa?threadID=1200448&tstart=0 

11/29/2007 10:38:50 PM

yeah, now that I look at my Activity Monitor, I see the same pattern. On my 100GB hard drive, I have 41.3GB free. My Virtual Memory is calculated at 40.5GB, and every one of my processes has at least 588MB of VM allocated to it. Looks to me like they might just take your free space on the drive and allocate it all out to the running processes in case it's needed

12/1/2007 1:39:19 PM