I tried building xorg from source with that patch but I had trouble installing it properly.
In the end, I installed the nouveau driver, which most definitely does not have this problem. xorg is no longer the bottleneck now. Thanks for the help!
PS: you are correct about the version of xorg I was using too.
Originally Posted by sarbash
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I guess you use last Xorg of version 1.11.*. If it is then you should try to downgrade Xorg to something like 1.10.* (in Debian is 1.6.*).
You're the one of many experiencing the performance regression with last Xorg. There are a few threads here about similar problems.
It's all about trapezoid acceleration. There is the unofficial path for temporary solution.
Please, be patient and wait for next driver update.
Or downgrade Xorg as suggested.
[/telepathy mode off]