Another Attempt At Reducing GNOME's Mutter Input Latency

[phoronix]

Phoronix: Another Attempt At Reducing GNOME's Mutter Input Latency

Prolific GNOME contributor Daniel Van Vugt of Canonical working to optimize the desktop stack for Ubuntu continues his great upstream-focused work on enhancing the performance of various key components. This past week he posted a new merge request that seeks to lower the input latency further for the Mutter compositor / window manager...

http://www.phoronix.com/scan.php?page=news_item&px=Another-Mutter-Input-Latency-2

[torturedutopian]

Thank you again, Daniel, great work !

My dumb user question : does this patch only affect windowed-apps or also fullscreen apps... (obviously I'm referring to games ;-) ?

[AsuMagic]

Thank you again, Daniel, great work !

My dumb user question : does this patch only affect windowed-apps or also fullscreen apps... (obviously I'm referring to games ;-) ?

AFAIK full screen apps are indirected so the compositor doesn't compose them. So it should not matter.

[treba]

AFAIK full screen apps are indirected so the compositor doesn't compose them. So it should not matter.

If I get things right, this MR is mostly about Wayland (see https://gitlab.gnome.org/GNOME/mutte...68#note_530925), but could be wrong here. In that case, fullscreen games would be affected as they don't yet get unredirected there. Although there's ongoing work by Jonas Adahl to make it work under Wayland, which might even land for 3.34 (the concept is quite different, though. The term 'unredirect' doesn't really apply. And event delivery would still be handled by the compositor, so this MR would still apply there).

[Britoid]

AFAIK full screen apps are indirected so the compositor doesn't compose them. So it should not matter.

I would think given this MR is about input latency, compositor output latency is not really relevant.

If I get things right, this MR is mostly about Wayland (see https://gitlab.gnome.org/GNOME/mutte...68#note_530925), but could be wrong here. In that case, fullscreen games would be affected as they don't yet get unredirected there. Although there's ongoing work by Jonas Adahl to make it work under Wayland, which might even land for 3.34 (the concept is quite different, though. The term 'unredirect' doesn't really apply. And event delivery would still be handled by the compositor, so this MR would still apply there).

Yeh. "Unredirection" doesn't really exist in the Wayland world in the same way. I think on Wayland it's more about the compositor getting as much out of the way as possible for full screen applications.

[tildearrow]

Oh, Daniel, you get a chance in mainline...

Time to try to upstream my efforts on the KWin side!

[RealNC]

My dumb user question : does this patch only affect windowed-apps or also fullscreen apps... (obviously I'm referring to games ;-) ?

Applications don't get their input events from the window manager, so I'd say this doesn't affect applications at all (fullscreen or not.)

[polarathene]

Oh, Daniel, you get a chance in mainline...

Time to try to upstream my efforts on the KWin side!

That'd be good! There was that other dev who had their own patch for rendering GTK apps with kwin frames or something too, but they weren't interested in trying to get it merged upstream into kwin

https://www.reddit.com/r/kde/comments/c7i5zr/kwin_with_gtk_frame_extents_support_sick/

[torturedutopian]

Oh, Daniel, you get a chance in mainline...

Time to try to upstream my efforts on the KWin side!

Please do ! :-)

[torturedutopian]

> Another performance patch got in. Yay.

Wow, patch description sounds simple but effective :-) That's surprising that wasn't the default behaviour !