Ubuntu 7.10 hogging RAM

[zer0]

I don't know why, but Ubuntu seems to be running very slowly lately. I'm running it on an older Dell Dimension with a 2.53ghz P4 and 1GB of RAM. Its idling with only Mozilla Thunderbird and two BitTornado clients running, and it seems to be using almost 1,000,000K of memory, however, none of the processes listed seem to be using a high percentage of memory, so I'm not really sure whats going on. Anyway. I took a screen shot of top running, since trying to redirect output to a text file didn't work out so well (I'm still learning...). I was hoping you guys might be able to take a look and possibly give me some insight here as to what's causing the high memory usage and how to cut it back, since my machine is really starting to crawl...

[SecretSquirrel]

In top, hit 'O' (capital oh) then select either 'n' or 'q' as the sort field. It is quite possible that you have some other "heavy" memory use processes that simply aren't showing up in the limited 'top' process list.

--SS

[Usacomp2k3]

Only 100mb out of 1024? What's the problem?

[titan]

Only 100mb out of 1024? What's the problem?

That's what I was thinking!
Until I realized he left out a zero and a comma. If you look at the top output it shows 977,172k used and only 57,756k free.

To the OP, try typing "free" at the command line and post its output here.

[bitvector]

Well, according top, 385M is for buffer cache, so that can be thought of as "free" memory, since it will be discarded when there is memory pressure. On an OS like Linux, all of your memory is going to be in use soon after you boot up by design (because whatever would be free will go to buffer cache).

The fact that all of your memory is "in use" isn't an issue by itself. However, you are using 631MB of swap. Just speculating, but some process (or processes) may have a large virtual memory footprint due to internal memory leaks where they leave large amounts of dead data in their address space but unfreed. Pages containing data that is dead to the application will eventually get paged out because they haven't been used in a long time. The OS doesn't know that they'll never be used again, so it has to save them in swap if it wants to remove them from RAM. You can try restarting various long-running apps to see if your swap footprint goes down a lot after certain ones terminate.

Also, why is your load average around 2? It doesn't look like it's from heavy CPU usage, so are there processes doing heavy I/O? That could give the system a sluggish feeling. Also, emerald looks like it is using a relatively large amount of memory (almost 250MB resident). Maybe you should turn off 3D desktop effects.

[notfred]

Don't worry about the memory side of things, Linux uses memory as cache for disk when it needs to and that is what you are seeing.

Almost half of your processor power is going into driving the fancy graphics effects, I would turn them off. Running two bittorrents is also causing a lot of drive activity (CPU is showing wait time), I bet if you do an "iostat -x 3" then you'll see a high disk utilisation. Killing off the 3d effects will help free some more memory for it to use as cache for the hard drive.

One other thought is how do you have your partitions mounted? If you are running ext3 then try adding the options "noatime,nodiratime,data=writeback" to them. I think Ubuntu does the noatime by default, but if it hasn't that can speed up your disk access substantially. The "noatime,nodiratime" apply to all fs types, the "data=writeback" is an ext3 speed optimisation at the expense of potentially having deleted data reappear after a crash - if your system doesn't crash it's safe to use.

[zer0]

try typing "free" at the command line and post its output here.

Code: Select all

             total       used       free     shared    buffers     cached
Mem:       1034928    1020456      14472          0       3024     292100
-/+ buffers/cache:     725332     309596
Swap:      1646620     746528     900092

Also, how do I turn off emerald? If I just disable window decorations through compiz, I have no title bars on any of my windows. How do I turn off emerald and just go back to using GNOME's themes?

[Usacomp2k3]

sudo apt-get remove emerald?

(note, I have no idea)

[zer0]

I'm just afraid that if I uninstall it, I won't be able to get my damned title bars back. Whenever I disable window decorations, they disappear. I'm worried that if I just uninstall emerald, it won't automatically revert back to the GNOME theme.

Anyone know for sure?

[Pilok]

I'm not a current linux user, but I'm quite sure that it you disable compiz, the window manager will return to metacity, meaning you will will be using gnome window decorations.

Perhaps this port of Scaled Black for metacity will help?
http://gnome-look.org/content/show.php/ ... tent=54773

[zer0]

Emerald seems to be the only thing sucking up memory. Compiz itself doesn't seem to be such a drain. Ideally, I'd like to ditch Emerald without losing compiz in the process. I might try to just remove emerald and hope for the best. If anyone has any ideas, by all means let me know, otherwise I'll just try doing that when I get the chance and see what happens...

[hypocratus]

You can switch by pressing alt+F2 to get a run dialog box and then type metacity --replace
This will switch the engine over to metacity. If you want to switch back to compiz then type compiz --replace
You might be able to switch your theme from emerald using the themes option which is under System->Preferences->Appearance
Hope that helps.

[bthylafh]

Mounting volumes with noatime is outdated as of Ubuntu 8.04. It automatically mounts volumes with relatime instead, which is a new option that only updates atime when it's IIRC more recent than the other times. Beats noatime because there are some programs (like mutt) that rely on atime for certain things.

[just brew it!]

Mounting volumes with noatime is outdated as of Ubuntu 8.04. It automatically mounts volumes with relatime instead, which is a new option that only updates atime when it's IIRC more recent than the other times.

Actually, it only updates it if the previous atime is older than the other times. Found a post at kerneltrap that explains it.

[bthylafh]

Ah. I thought that sounded a bit wrong.