[SOLVED] What is taking up so much memory?

elmer_42 · 2008-11-07 01:30:39

As you can see by the screenshot at the end of my post, my RAM is being eaten up. That's htop, and I have it sorted by memory percentage, but even the app using the most RAM is not even taking up 2% of it. I first recognized this problem a few days ago, but it may have been around for longer than that. If I reboot, of course, memory usage goes down, but that seems to be the only solution to the problem. What do you think is going wrong? Has anybody else had this problem? Should I try taking out the two 512MB DIMMs of DDR2 667, leaving 2GB of DDR2 800, and see if that helps?

Last edited by elmer_42 (2008-11-07 02:23:48)

fukawi2 · 2008-11-07 01:35:33

Maybe this is the "problem"?
http://www.linux.com/forums/topic/3246

elmer_42 · 2008-11-07 02:23:32

Hm. That works, thanks! The only weird thing I noticed is that you have to su and then run the command; a simple sudo will not work. But that's OK by me. Thanks for the help.

skottish · 2008-11-07 02:30:09

elmer_42 wrote:

Hm. That works, thanks! The only weird thing I noticed is that you have to su and then run the command; a simple sudo will not work. But that's OK by me. Thanks for the help.

There's no need to clear the cache. It's one of the reasons why Linux performs so well. The kernel will take care of it.

fukawi2 · 2008-11-07 03:08:57

elmer_42 wrote:

Hm. That works, thanks! The only weird thing I noticed is that you have to su and then run the command; a simple sudo will not work. But that's OK by me. Thanks for the help.

Because of the redirect
http://forums.macosxhints.com/showthread.php?t=5010

elmer_42 · 2008-11-07 04:41:58

skottish wrote:

The kernel will take care of it.

If it does, then why is it using so much RAM? Is there a logical purpose?

fwojciec · 2008-11-07 05:04:07

elmer_42 wrote:

skottish wrote:
The kernel will take care of it.
If it does, then why is it using so much RAM? Is there a logical purpose?

It is easier/faster to load things from memory cache rather than from the hard drive -- so it makes perfect sense to let kernel store in memory what it would otherwise have to load and reload time and again from the hard drive.

creslin · 2008-11-07 05:19:06

`free | grep buffers` will give you a much clearer picture of how much memory is being used. Clearing your buffer cache hurts your system performance. As has been said, reading from memory is much quicker than reading from hard disk, so the kernel maximizes performance by utilizing the "free" (not actively being used) memory for disk buffering.

Last edited by creslin (2008-11-07 05:21:14)

skottish · 2008-11-07 05:28:01

elmer_42 wrote:

skottish wrote:
The kernel will take care of it.
If it does, then why is it using so much RAM? Is there a logical purpose?

See the other replies for the answer.

The green lines in htop are the ones that you need to be concerned about. That's the same as the first value in the memory line. You're looking really good on memory in that screenshot.

elmer_42 · 2008-11-07 14:28:33

Oh, I see. Thanks, guys, for explaining it to me. It just sort of freaked me out when I noticed that I had barely any free RAM. I will not be clearing my cache any longer now that I know it is helpful.

miggy · 2008-11-07 20:34:11

PS, I'd be more concerned about the 40% CPU usage of mpd

elmer_42 · 2008-11-07 23:30:26

Yeah, I noticed that, too. I'm not sure why it was like that, because now it only uses 1-3% of the CPU, which is very good in my opinion.

Arch Linux

#1 2008-11-07 01:30:39

[SOLVED] What is taking up so much memory?

#2 2008-11-07 01:35:33

Re: [SOLVED] What is taking up so much memory?

#3 2008-11-07 02:23:32

Re: [SOLVED] What is taking up so much memory?

#4 2008-11-07 02:30:09

Re: [SOLVED] What is taking up so much memory?

#5 2008-11-07 03:08:57

Re: [SOLVED] What is taking up so much memory?

#6 2008-11-07 04:41:58

Re: [SOLVED] What is taking up so much memory?

#7 2008-11-07 05:04:07

Re: [SOLVED] What is taking up so much memory?

#8 2008-11-07 05:19:06

Re: [SOLVED] What is taking up so much memory?

#9 2008-11-07 05:28:01

Re: [SOLVED] What is taking up so much memory?

#10 2008-11-07 14:28:33

Re: [SOLVED] What is taking up so much memory?

#11 2008-11-07 20:34:11

Re: [SOLVED] What is taking up so much memory?

#12 2008-11-07 23:30:26

Re: [SOLVED] What is taking up so much memory?

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