Comment # 13 on bug 92996 from Ernst Sjöstrand

I have xserver 2:1.17.2-1ubuntu9
and
xserver-xorg-video-amdgpu 1.0.99+git1511200733.43c2dc~gd~w
with DRI3 enabled now.

Doesn't help, very bad interactivity during Unigine Heaven and vsync
does not work during and after running Heaven.