Hi!

What is the expected performance of KWin? I have a very new computer (quad core Intel + NVidia 560 Gti + 8 GB RAM) and things like the kickoff launcher or getting the window back after minimizing are not smooth. This is confirmed by the fps tool: fps go below 30.

Futhermore, I had the feeling that Gnome 3 on a much older computer runs very smoothly.

Any advice? I use the proprietary NVidia driver with KDE 4.7.1.

Cheers

I don't think KWin is smooth on *any* computer for many people; there are quite a few threads about this. I have similar problems to you: a pretty high end system w/ the proprietary nVidia driver, but still a lot of stuttering and jerking with certain effects, especially the desktop cylinder. Minimizing windows is smooth for me though.

If it runs on your system you can try Compiz instead, which is totally smooth even on old or low end hardware with every effect or setting you can throw at it. Unfortunately it doesn't integrate as well with KDE, but it's usable and much, much smoother overall. I do hope the KWin performance will improve in the future, because obviously KWin is the best thing to use with KDE as far as how nicely it integrates.

One thing you can try is to turn off transparency effects. It didn't help for me, but but some people say it helped KWin be smoother for them.

Cheers...

Thanks for clarifying.

I would be interested, from a technical point of view, why there is such a problem. Recent hardware should be more than enough powerful to handle some little desktop effects, right? I mean compared to games.... So are the drivers to be blamed? And compiz people work around the problem?

Recent hardware should be more than enough powerful to handle some little desktop effects, right? I mean compared to games.... So are the drivers to be blamed? And compiz people work around the problem?

Well, I don't work on KWin, and have never even seen that code, so I can only give you my guess. Please be aware that I might be *totally* off in space about this. Do not take this as anything but a guess.

I have, at least, done significant OpenGL 3.0 programming on Linux under the proprietary nVidia drivers, and from what I can tell, the drivers are pretty good. Sure, there are little things here and there, but nothing that I'd call a big problem, and that includes significant use of GLSL and the more advanced GL APIs. My guess is rather than KWin is implemented in an inefficient way. With Graphics APIs, there are sometimes ways to do the same things some of which are literally orders of magnitude faster than others.

Many times I've seen people complain about performance, and when you look at the code, they're doing X, where if they did Y instead, they'd see it run 50 times faster or some such. It's quite possible that Compiz is simply using the OpenGL API in a much better way than KWin is.

Given that KWin is open source, in theory I could look at it if I had time, but I'm afraid I don't .

All that being said, I'm still glad for KWin. It isn't perfect, but it integrates very well with the rest of KDE.

Use raster: http://kde-apps.org/content/show.php?content=129817
It makes a huge difference on my system. And play with different settings in Desktop effects settings. Turn off one by one: blur, opengl2 shaders, vsync etc and test.

By default effects work terrible on my laptop with ati card. But after some tweaking I have now very smooth and fluid effects.