Re: kwin: XRender "slow" (as usual), OpenGL much slower (new problem)
Ok, this problem definitely has something to do with kwin built from trunk. Installed kwin-4.2.2 (mixed it with my normal system which is quite unstable but it is able to do enough to compare the performance) and OpenGL performance there seems completely normal (X cpu usage at ~4%).
Will report this at bugs.kde.org later tomorrow.
But is this definitely a kwin bug or could it be some OpenGL interaction issue (which iirc happened before around the time kwin compositing got implemented, according to the driver release notes).
Anyone else who is able to test a kwin svn build with nvidia drivers?