Version: (using KDE 4.0.83) Installed from: Fedora RPMs OS: Linux One specific transition effect of the slideshow screensaver, when used, makes kwin to consume 95% or more of CPU processing time and kind of freeze. The effect is the one in which dots of the new image appear over the old one until the new image is fully displayed. It seems kwin does not really freeze, but becomes EXTREMELY slow. It's possible that, given enough time, the transition finishes and the system gets back to normal, but I don't know for sure. I say that because sometimes, when I get back to the computer after many hours away, the screensaver is still running ok. However, if I wait until this specific transition effect is used, the said problem occurs. Even if things do go back to normal if one wait enough, this is not feasible, as it takes too much time. To regain control over the GUI, it's necessary to kill X using CTRL+ALT+BS and login again. However, it's still possible to switch to a text console using CTRL+ALT+Fx. I'm running Fedora 9 with a nvidia GeForce FX 5500 graphics card and proprietary nvidia drivers packaged by livna and have no other graphic related problems, using 3D acceleration or not. Let me know if there's some other information I can provide to help with the solution.
I have the same problem with 4.0.98 if you kill kwin from a text console, everything goes back to normal, but this error still makes the slide show screensaver unusable, and because of that this should be fixed beore the final release. it also occurs if you run kslideshow.kss from a console and let it run in a window. This way though it recovers and shows the next picture after freezing in the transition effect for one picture's time.
I do believe there are other things that are more important to be fixed and that take time from developers. However, why not just disable this effect while it's not possible to fix it? At least the screensaver would be usable.
yeah there certainly are other more important things, but then the screensaver should simply be disabled for the release. otherwise there will be lots of people complaining about it. well you can't disable these effects in the settings (at least i couldn't find the option), but of course if simply this speical effect is disabled in the code the screensaver would be usable again, so maybe that could be a temporary solution. I will look at the code and maybe create a patch doing just that tomorrow.
Yes, that's what I meant, disabling this effect in the code. It was a suggestion for the developers. For me, this would be a totally satisfactory work-around until this effect can be fixed. If you (Niklas) know how to do that, please do :)
yeah, i will look at it tomorrow, i just don't have the time now, since i have a rather important exam tomorrow morning ;) anyway i highly doubt that it will be included in 4.1 final, it's probably just too late... but well, hopefully 4.1.1 then
Created attachment 26200 [details] simple patch to disable effectRandom about the simplest patch of them all: simply commented out the registraion of the effectRandom, which is the effect that causes kwin to freeze. it's just a one liner, so maybe it can get included in 4.1 final, since it makes ksildeshow.kss usable again, and would save KDE from quite a few complaints i could imagine
Thanks for patching! Let's hope it will be included in 4.1. Hope you've done well on your exam :)
*** This bug has been marked as a duplicate of 163643 ***
This bug is partially solved, i.e., kwin does not freeze anymore (KDE 4.1.3, Fedora 10 packages). However, this specific transition effect is still too slow. Even when I press a key while it's running, it takes 5 to 10 seconds before the screensaver stops running and the desktop is available again. Is this something that can be fixed in bug 163643, of which this has been marked as a duplicate, or is it something to be fixed in the screensaver itself?
Bug 163643, of which this has been made duplicate, is marked as solved. Indeed, kwin does not freeze anymore when this transition effect runs. However, as of KDE 4.1.4, everything becomes EXTREMELY slow when this transition effect runs and it takes a lifetime to finish. Also, when it's running and a key is pressed or the mouse is moved, it takes up to ten seconds until it stops and the desktop is available again. The transition is so slow and takes so much time to complete that it's no surprise that almost every time I sit at the computer, this transition is running and I have to wait 10 seconds until it stops after I press any key. The slideshow screensaver is still unusable, as it gets stucked with two pictures overlaped every time this transition effect runs. Wouldn't it be better just to disable this transition, using the patch provided in comment #6? At least we could use slideshow screensaver again. Should I close this bug again and open another for this issue? Thanks.
> Indeed, kwin does not freeze anymore when this transition effect runs. Then don't reopen this one and fill a new bug report please. *** This bug has been marked as a duplicate of bug 163643 ***