It is possible to display frames per seconds metric in the gnome shell. First create a file /usr/share/wayland-sessions/gnome-wayland-fps.desktop
[Desktop Entry]
Name=GNOME on Wayland (fps)
Comment=Debug version of gnome, displaying fps
Exec=/usr/bin/env CLUTTER_SHOW_FPS=1 /usr/bin/gnome-session
Type=Application
DesktopNames=GNOME
X-GDM-SessionRegisters=true
Log out, and log into the new session GNOME on Wayland (fps). In the new session, open terminal and launch command:
sudo journalctl --followThe FPS measurement will be printed every few seconds. Very low values (1-2 FPS) are printed if the session is idle. To test the performance, open some windows, then keep pressing windows button to show and hide overview. Or keep windows pressed and keep pressing arrow buttons to move the window around the screen.
This is an example output:
jan 14 12:14:41 wall-e gnome-shell[12525]: *** HDMI-1 frame timings over 1,0s: 16,46 FPS, average: 1,9ms, peak: 3,7ms
jan 14 12:14:42 wall-e gnome-shell[12525]: *** HDMI-1 frame timings over 1,0s: 20,33 FPS, average: 1,9ms, peak: 2,4ms
jan 14 12:14:43 wall-e gnome-shell[12525]: *** HDMI-1 frame timings over 1,0s: 22,25 FPS, average: 1,3ms, peak: 2,8ms
jan 14 12:14:44 wall-e gnome-shell[12525]: *** HDMI-1 frame timings over 1,0s: 20,30 FPS, average: 1,8ms, peak: 2,5ms
jan 14 12:14:45 wall-e gnome-shell[12525]: *** HDMI-1 frame timings over 1,0s: 20,34 FPS, average: 1,8ms, peak: 2,5ms
jan 14 12:14:46 wall-e gnome-shell[12525]: *** HDMI-1 frame timings over 1,0s: 22,27 FPS, average: 2,1ms, peak: 3,2ms
jan 14 12:14:47 wall-e gnome-shell[12525]: *** HDMI-1 frame timings over 1,0s: 25,82 FPS, average: 1,7ms, peak: 3,4ms
jan 14 12:14:48 wall-e gnome-shell[12525]: *** HDMI-1 frame timings over 1,0s: 21,42 FPS, average: 2,0ms, peak: 3,0ms
jan 14 12:14:49 wall-e gnome-shell[12525]: *** HDMI-1 frame timings over 1,0s: 25,16 FPS, average: 2,2ms, peak: 2,7ms
jan 14 12:14:50 wall-e gnome-shell[12525]: *** HDMI-1 frame timings over 1,1s: 18,75 FPS, average: 2,0ms, peak: 2,6ms
This is an integrated GPU Intel® HD Graphics 4600 on 4K display. You can see the performance is poor.