Changing desktop background eats up all available CPU time

change status: New -> Incomplete

Can you please share more information regarding this problem?

I have not been able to reproduce it on my 9.04 setup running on a nVidia GeForce Graphics Card.

Can you share your driver + Hardware details and also xorg.conf and the dmesg output.

Graphics card is onboard intel Intel(R) G45/G43, driver is intel.

do you use compiz? could you disable it and test? could you execute top and see what process is using that amount of cpu while changing the desktop? There's no indication of that on the report.

The process that's consuming the CPU time is /usr/X11R6/bin/X11. I'm using Compiz.

If I disable compiz, is there a way to reenable it without losing my customized configuration (created with compiz settings manager)? I think if I set the Visual Effects (in the Appearance panel) to "None" and then back to "Normal", I will loose them.

Marking bug report as confirmed and changing package to xserver-xorg-video-intel.

Same bug here, just installed Ubuntu 9.04 yesterday, I was using wallpaper-tray from synaptic and as usual set it so that my wallpaper change every minute and I found that every minute, in top, Xorg took up to 97% of my CPU and was lagging the whole system for about 5 to 15 seconds. It do appear it is because of the fade in effect when changing wallpaper because it worked great with Ubuntu 8.10 and there wasn't any fade effect. I am using a GeForce FX 5600 with the proprietary drivers and in visual effects in Appearance I selected None (so no compiz).

I tried using Option "MigrationHeuristic" "greedy" and Option "UseEvents" "on" in section Device in xorg.conf but to no avail.

Here's the line from top that shows it :
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
2641 root 20 0 88988 52m 9420 R 97.6 10.6 1:37.32 Xorg

My xorg.conf is quite simple :
Section "Device"
    Identifier "Configured Video Device"
    Driver "nvidia"
EndSection

Section "Screen"
    Identifier "Default Screen"
    Device "Configured Video Device"
    Monitor "Configured Monitor"
    DefaultDepth 24
    Option "AddARGBGLXVisuals" "True"
    Option "NoLogo" "True"
    SubSection "Display"
        Depth 24
        Modes "nvidia-auto-select"
    EndSubSection
EndSection

[This is an automatic notification.]

A new major version of the -intel driver is now available in Karmic.

This version includes a major reworking of the acceleration
architecture, which resolves a huge number of issues. We do not know
whether it resolves the issue you reported.

Would you mind testing Karmic Alpha-2 and seeing if it is still a
problem? CD ISO images are available here:

  http://cdimages.ubuntu.com/releases/karmic/

If the issue can still be reproduced on karmic, please report here with
your findings, and attach a fresh Xorg.0.log from your test, and we will
be able to forward the bug upstream.

Otherwise, if the bug no longer exists in Karmic, let us know that as
well.

In the off chance you encounter different bugs while attempting to test
Karmic, please report those as new bug reports.

I just discovered that (in Jaunty), changing the acceleration method to UXA considerably reduces the impact of this bug (the above sequence only takes about 3 seconds now).

I'm going to try the Karmic image soon.

I tried to test this with Karmic, but I couldn't really get any conclusive results. Basically, the screen is broken at all times. Windows "loose" their decorations randomly, moving them around produces artifacts, and the whole system behaves really sloppy. So there was no real way to tell if things got worse while changing the background.

Okay, can you attach a Xorg.0.log and dmesg (and maybe a photo showing the screen corruption if possible) from Karmic after reproducing the issue?

I just booted into alpha2 again, and miraculously this time everything worked. No screen corruption, no problems with changing background. Strange...

Thanks for letting us know the issue is resolved.