Quote Originally Posted by gedgon View Post
And when exactly (OpenGL composited) KWin offloading CPU for windows management under X? Since backing store is here, it uses more CPU cycles even for moving windows.
I'm not completely sure what you were trying to say – seems one or more words are missing. Fact is, the X process uses lots of CPU power when moving windows without compositing (on my hardware ~40%). With compositing and despite the use of several effects (shadow, fade, and transparency) the X process stays around 4% with a short spike to 8%.