g-s-d uses high disk i/o

[Josh Headapohl]

Binary package hint: gnome-settings-daemon

Sometimes after logging in, g-s-d pegs my disk. When I run iotop, I can see gnome-settings-daemon going as fast as it can for maybe five or ten seconds, then it goes back to normal.

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: gnome-settings-daemon 2.30.0-0ubuntu6
ProcVersionSignature: Ubuntu 2.6.32-21.32-generic 2.6.32.11+drm33.2
Uname: Linux 2.6.32-21-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
Date: Sat May 1 21:48:34 2010
EcryptfsInUse: Yes
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: gnome-settings-daemon

[Chris Coulson (chrisccoulson)]

Thanks, but that's not a bug. gnome-settings-daemon cleans your thumbnail cache some time after logging in, and that is where the IO comes from

[Milan Knizek (knizek)]

It would be nice if g-s-d cleans the cache with very low I/O priority to avoid slowing down other applications, which want to read from the disk - e.g. firefox almost freezes during g-s-d activity. (In my case, g-s-d runs almost half a minute each time I log in and computer is very unresponsive.)

[Brendan_P (brendan-p)]

This causes a performance issue for me to. Very heavy IO which negatively impacts the whole system.

[Kamil Páral (kamil.paral)]

This is definitely a bug, and an important one. Recently I started to suffer from these symptoms too. After starting up the computer and running nautilus (this is important, only after running nautilus), the gnome-settings-daemon process froze up my computer, totally. Disk spinning. It unfroze only after a long time. Very bad experience.

After reading this bug, I finally found the cause. Thumbnails directory. These are my measurements:

$ du -sh .thumbnails/
315M .thumbnails/
$ find .thumbnails/ | wc -l
14648
Time spent with 100% I/O load caused by g-s-d (after starting nautilus): 1min 45sec

That means every boot I had to wait 2 more minutes to be able to work with computer.

After removing ~/.thumbnails directory the problem is gone. Now my computer works fast again, finally.

Gnome-settings-daemon must *not* read all the thumbnails on nautilus start. It must expect there are a lot of them!

Note: 'find' command was able to count the thumbnails quickly. But when opening the directory with 'mc', it also took about two minutes. I suppose that g-s-d is doing something similar to mc, like calling 'file' on every file or similar task. That must be fixed (or otherwise g-s-d devs should make sure there are never dozens of thousands of files in that directory).

Please increase the priority on this.

[How to catch a fish (z-admin-how2catchafish-com)]

This is a continuing problem for me too. Every restart I have to reschedule gnome-settings-daemon to "idle" or it grinds my system to a halt on start-up for minutes on end.

In-case it helps someone else, I do the following:

$ ps -A|grep gnome-settings-daemon

- This will give you it's PID

$ ionice -c3 -p 1234

- Substitute 1234 for your PID
- Schedules the process 1234 to "idle" (lowest I/O priority)

[Roland Hieber (rohieb)]

See also #505085. Eric Link supported a workaround there (in comment 13) with a cron rule purging the files much more efficiently than g-s-d does.