https://bugs.freedesktop.org/show_bug.cgi?id=71134
--- Comment #7 from Michel Dänzer michel@daenzer.net --- (In reply to comment #6)
pixel offset on diagonal (which appears to be in opengl apps too): http://youtu.be/jTnI446eD-Q
If you mean the diagonal tearing visible on the stairs while moving, there's currently no way to avoid that with glamor other than running in fullscreen with page flipping enabled.