GNOME on Xorg seems to use the lowest refresh rate among monitors (non-NVIDIA GPUs)
Affected version
OS: Arch Linux
Mutter: 3.38.3, with performance patches from aur/mutter-performance. Regular Mutter is still affected, though.
As already stated in the title, this is an X.org issue. This, unlike #1470, concerns non-NVIDIA graphics cards.
GPU: AMD Radeon RX Vega 56
Drivers: Mesa 20.3.4
Bug summary
I'm running two monitors, both 1920x1080, one 144Hz, the other 60Hz. Just like in the issue mentioned above, running GNOME on Xorg seems to make Mutter render its animations at 60 fps, which is the lowest refresh rate among the two monitors.
This does not happen on Wayland, but there is another bug that I'm yet to report that prevents me from using it daily.
Steps to reproduce
- Have two monitors with different refresh rates
- Run GNOME on Xorg
- Open Activities, or really do anything such as moving windows around
What happened
On the 144Hz monitor, the refresh rate seems too low during animations. In fact, they seem to be running at 60 fps, which would match the other monitor's refresh rate, but I have not measured this exactly. Moving a window across both monitors seems to sync perfectly with regards to refresh rate, which is where my belief comes from.
What did you expect to happen
The animation framerate should be 144 fps to match the high refresh rate monitor.
Relevant logs, screenshots, screencasts etc.
None.