I recently realized that Compiz on my Ubuntu 12.04, was cosuming between 20% and 30% of my CPU even if I’m doing anything that requires graphical ressources. This was reported to launchpad; although, the problem is not yet resolved, but there is a little trick, which I’m going to show you, that can solve it.
Before I applyed this trick, this is how my system monitor used to look like:
To start, install compizconfig-settings-manager, then open it trough the dash.
Now click on OpenGL plugin to configue it
Then uncheck “Sync To VBlank”. you might want to select “Fast” in Texture Filter.
That’s it. Compiz now won’t consum too much CPU.
EDIT - This issue affects ATI video cards only.