PRIME and PRIME Synchronization
@rocha.ab: does setting the environment variable __GL_SYNC_DISPLAY_DEVICE help?
@rocha.ab: does setting the environment variable
__GL_SYNC_DISPLAY_DEVICE
help?

Posted 01/01/2018 08:59 PM   
What should I set it to?
What should I set it to?

Posted 01/01/2018 09:54 PM   
The connector name of the 144Hz monitor as seen in Xorg logs or xrandr, e.g. __GL_SYNC_DISPLAY_DEVICE=DFP-1
The connector name of the 144Hz monitor as seen in Xorg logs or xrandr, e.g.
__GL_SYNC_DISPLAY_DEVICE=DFP-1

Posted 01/01/2018 10:33 PM   
It didn't work. Thanks for the tip. But I'm not really willing to keep investigating it further. I'm gonna return the laptop and get another hardware. Thanks.
It didn't work.

Thanks for the tip. But I'm not really willing to keep investigating it further. I'm gonna return the laptop and get another hardware.

Thanks.

Posted 01/01/2018 11:15 PM   
I have this strange behaviour: I have a laptop with NVIDIA PRIME. modeset is enabled. The display supports frequencies from 20 to 100 hz in xrandr I have 1920x1080_100.00 99.90* where it is: 1920x1080_100.00 (0x225) 302.500MHz -HSync +VSync h: width 1920 start 2072 end 2280 total 2640 skew 0 clock 114.58KHz v: height 1080 start 1083 end 1088 total 1147 clock 99.90Hz but with glxgears I have 2 problems: 1) setting vsync in glsgears seems not to affect the ouput. 2) if I set PRIME SYNCHRONIZATION to 0, glgears goes over 20000 fps. Running synchronized to the vertical refresh. The framerate should be approximately the same as the monitor refresh rate. 100395 frames in 5.0 seconds = 20078.984 FPS 102430 frames in 5.0 seconds = 20485.918 FPS 101681 frames in 5.0 seconds = 20336.127 FPS 3) if I set PRIME SYNCHRONIZATION to 1 (or anthing different than 0) I get 60 fps Does anybody know why it doesn't sync to 100hz? (same with other refresh rates)
I have this strange behaviour:

I have a laptop with NVIDIA PRIME.
modeset is enabled.
The display supports frequencies from 20 to 100 hz

in xrandr I have
1920x1080_100.00 99.90*

where it is:
1920x1080_100.00 (0x225) 302.500MHz -HSync +VSync
h: width 1920 start 2072 end 2280 total 2640 skew 0 clock 114.58KHz
v: height 1080 start 1083 end 1088 total 1147 clock 99.90Hz

but with glxgears I have 2 problems:
1) setting vsync in glsgears seems not to affect the ouput.
2) if I set PRIME SYNCHRONIZATION to 0, glgears goes over 20000 fps.

Running synchronized to the vertical refresh. The framerate should be
approximately the same as the monitor refresh rate.
100395 frames in 5.0 seconds = 20078.984 FPS
102430 frames in 5.0 seconds = 20485.918 FPS
101681 frames in 5.0 seconds = 20336.127 FPS

3) if I set PRIME SYNCHRONIZATION to 1 (or anthing different than 0) I get 60 fps

Does anybody know why it doesn't sync to 100hz? (same with other refresh rates)

Posted 01/08/2018 01:35 PM   
@Zibri_ This might also depend on the compositor you are using, e.g. compiz can be manually set with ccsm or mutter with CLUTTER_DEFAULT_FPS. See what happens if you run glxgears fullscreen glxgears -fullscreen Also try with plain X. Create a file ~/.xinitrc containing [code]xrandr --setprovideroutputsource modesetting NVIDIA-0 xrandr --auto xterm & exec xterm [/code] Switch to VT, then run startx -- :5 You should get an X screen with xterms. There, run glxgears again.
@Zibri_
This might also depend on the compositor you are using, e.g. compiz can be manually set with ccsm or mutter with CLUTTER_DEFAULT_FPS. See what happens if you run glxgears fullscreen
glxgears -fullscreen
Also try with plain X. Create a file ~/.xinitrc containing
xrandr --setprovideroutputsource modesetting NVIDIA-0
xrandr --auto
xterm &
exec xterm

Switch to VT, then run
startx -- :5
You should get an X screen with xterms. There, run glxgears again.

Posted 01/09/2018 10:08 AM   
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