Comme=
nt # 45
on bug 10617=
5
from rropid@gmail.com
(In reply to bmilreu from comment #43)
> If devs want an easy test case, use these links =
for reproducing it in
> chromium:
>=20
> https://www.vsynctester.com/<=
/a>
> https://www.testufo.com/phot=
o
> https://www.slither.io
>=20
> move the cursor around, move/resize some windows. you will notice it
>=20
> the vsync/cursor stutters and frame-skips are pretty noticeable with d=
c=3D1 on
> all three links
>=20
> KWin, compton, TearFree, mutter, xfwm4 all have the same problems.
I just tried dc=3D1 and I only seem to have a problem if I use TearFree. Th=
ings
are totally fine without TearFree.
To be clear about what I'm doing here right now:
I made sure DC is enabled:
$ systool -vm amdgpu | grep dc
dc =3D "1"
$ dmesg | grep -i display
[ 1.014297] [drm] Display Core initialized with v3.1.59!
I removed TearFree from my X config:
$ cat /etc/X11/xorg.conf.d/20-amdgpu.conf=20
Section "OutputClass"
Identifier "my amdgpu settings"
MatchDriver "amdgpu"
Option "DRI" "3"
EndSection
And I started Compton like this to make sure it's a clean config:
$ compton --config /dev/null --backend glx --vsync opengl
With this setup, I don't seem to have any stutter. I visited the websites y=
ou
mention in a Chromium window, then opened another window and tried moving
things around and resizing. It behaves fine, same as what I know from norma=
lly
using dc=3D0.
Kernel is 4.19.2, Mesa 18.2.4, Xorg 1.20.3, the GPU is a RX480, monitor is =
60
Hz.
After I had typed this, I have now added TearFree to the X config and resta=
rted
X:
$ cat /etc/X11/xorg.conf.d/20-amdgpu.conf=20
Section "OutputClass"
Identifier "my amdgpu settings"
MatchDriver "amdgpu"
Option "TearFree" "true"
Option "DRI" "3"
EndSection
Now, with TearFree enabled, things are super terrible. Trying to move a win=
dow
around has extreme stutter, it seems to drop frames. If I restart Compton w=
ith
"GALLIUM_HUD=3Dfps" and then try moving a window around in circle=
s, I can see it
stays below 40 fps instead of hitting the 60 fps that it should be running =
at.