Comment 23 for bug 770160

I've found a rather easy workaround. I simply had to disable the following option in the Device section of my /etc/X11/xorg.conf (see the attached file) so that vline doesn't wait for non-pageflipped swap buffers:

Option "SwapbuffersWait" "False"

Remeber to restart the xserver afterwards (e.g. log in and log out) and moving windows shouldn't be slow any more. I can't see any regressions after doing this.

Note: this works with the radeon driver but should also work with intel. I'm not sure how to do the same with proprietary drivers.