Performance degradation after KDE runs for sometime

[Marko Vojinovic]

On Friday, November 12, 2010 17:25:55 Armelius Cameron wrote:
> Hello,
> I've been noticing that KDE performance degrades after it runs for a while
> on my machine. Since I am the only user, I usually never log off, and just
> let KDE runs for days at a time

+1

I think I see the same issue. I reported it on the main Fedora list, here's a 
link to the thread:

http://comments.gmane.org/gmane.linux.redhat.fedora.general/381446

My setup seems to be fairly different from yours (F12 64bit KDE with Compiz, 
Intel 965 graphics hardware), but the symptoms seem to match.

I traced the issue down to swap usage --- after a couple of days of running, 
*something* seems to gradually fill the memory with junk, so the system starts 
swapping more and more for regular desktop apps. I suggest you take a look at 
swap usage when you start feeling a performance hit. Logging off and back on 
helps (and cleans out the swap), but eventually it gets filled up again.

I wasn't able to pinpoint which particular app is responsible for memory 
leakage (it is definitely an X app since relogging restarts X and everything is 
fine again), but we may be able to help each other if we cross-reference which 
apps we both typically keep open/use regularly.

It is curious that compiz somehow avoids being swapped out, so is always 
responsive (in my case), while KDE desktop effects in your case seem to get 
sluggish with the rest of the system. I haven't tried KDE desktop effects on 
this machine.

After some time spent on this, I decided to upgrade to F14 next week, hoping 
that the issue might go away. But I am not sure it will.

> I am just wondering if anyone else see the same thing. I am curious if this
> is KDE's problem, or X with/or Nvidia-driver interaction.

If we are seeing the same issue, you can rule out nVidia driver, since I don't 
have it on this machine. My KDE is 4.4.5, from a fully updated F12.

I'm pretty baffled with this myself, so if you happen to find out anything 
related, I'm all ears! :-)

HTH, :-)
Marko