Bug 512969

Summary:	Some games wont activate async/tearing
Product:	[Plasma] kwin	Reporter:	pollux/ned <pollux66>
Component:	wayland-generic	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	NEEDSINFO WAITINGFORINFO
Severity:	normal	CC:	xaver.hugl
Priority:	NOR
Version First Reported In:	6.5.3
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description pollux/ned 2025-12-05 07:03:18 UTC

SUMMARY
I have noticed when enabling kwin with debug that some games dont make kwin switch to async/tearing in fullscreen

These games so far are

Arc Raiders

THE FINALS

Halo Infinite

Minecraft

STEPS TO REPRODUCE
1. Play those games with kwin debug enabled
2. Set adaptive sync to never so it should switch to async in fullscreen games
3. Notice that it doesnt switch to async and stays on vsync even when vsync is turned off in the graphics or display settings

OBSERVED RESULT
Async doesn't happen and instead stays on vsync which causes input latency, important for lowest latency for the finals or halo infinite because it is a fps where frames mean everything in some cases.

EXPECTED RESULT
Async to be applied to those games when adaptive sync is set to never

SOFTWARE/OS VERSIONS
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: Cachyos
KDE Plasma Version: 6.5.3
KDE Frameworks Version: 6.20.0
Qt Version: 6.10.1

ADDITIONAL INFORMATION

Comment 1 pollux/ned 2025-12-05 07:39:33 UTC

I forgot to add adaptive sync works 100% the time in the testing of many games and switches back to vsync when you are not in the game so i wonder whats going wrong that it doesnt want to do async.

Comment 2 Zamundaaa 2025-12-05 14:32:32 UTC

Minecraft uses OpenGL, which unfortunately just has no API to request tearing.

If you force tearing on these games with a  window rule, does it work then?

Comment 3 pollux/ned 2025-12-05 15:27:37 UTC

(In reply to Zamundaaa from comment #2)
> Minecraft uses OpenGL, which unfortunately just has no API to request
> tearing.
> 
> If you force tearing on these games with a  window rule, does it work then?

yes that does indeed work with a window rule

Comment 4 Zamundaaa 2025-12-05 15:30:39 UTC

Then the problem is with the apps not requesting tearing themselves. Are you perhaps on Nvidia? I've seen a few complaints about this with the proprietary Nvidia driver, likely something regressed in it.

Comment 5 pollux/ned 2025-12-05 15:44:33 UTC

(In reply to Zamundaaa from comment #4)
> Then the problem is with the apps not requesting tearing themselves. Are you
> perhaps on Nvidia? I've seen a few complaints about this with the
> proprietary Nvidia driver, likely something regressed in it.

nope, RX 6700 10GB

Minecraft has been resolved also by using zink instead of opengl

Comment 6 Bug Janitor Service 2025-12-20 03:46:27 UTC

🐛🧹 ⚠️ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

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