Bug 511423

Summary:	DE feels little choppy with KWIN_USE_OVERLAYS=1 and kwin 6.5.1
Product:	[Plasma] kwin	Reporter:	timon2201
Component:	performance	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	major	CC:	xaver.hugl
Priority:	NOR
Version First Reported In:	6.5.1
Target Milestone:	---
Platform:	CachyOS
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description timon2201 2025-10-31 12:28:30 UTC

SUMMARY

When using kde 6.5.1 with kwin 6.5.1 and  KWIN_USE_OVERLAYS=1 set then the whole desktop feels little choppy. I can really explain it but it feels like the framerate pacing is off. You can also feel it when you just move the cursor on the screen. 

i am not sure if this is related to the bug https://bugs.kde.org/show_bug.cgi?id=489952

But what i can say is that when i downgrade kwin from 6.5.1 to 6.4.91 then everything is very smooth and the inconsistencies are gone. I didn't try it yet with kwin 6.5.1 and KWIN_USE_OVERLAYS=0 .

I found this when i downgraded kwin to 6.4.9 to workaround the mouse courser stuck on screen bug, for the game arc raiders, which is already fixed.

STEPS TO REPRODUCE
1.  Start some game and play or just move the cursor around the screen. 

OBSERVED RESULT
little choppy movement, inconsistent framepacing ( idk if it is really framepacing but it feels kinda off)

EXPECTED RESULT
smooth. like with kwin 6.4.9

SOFTWARE/OS VERSIONS
Operating System: CachyOS Linux 
KDE Plasma Version: 6.5.1
KDE Frameworks Version: 6.19.0
Qt Version: 6.10.0
Kernel Version: 6.17.3-273-tkg-eevdf-llvm (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 5800X3D 8-Core Processor
Memory: 32 GiB of RAM (31,3 GiB usable)
Graphics Processor: AMD Radeon RX 7900 XTX
Manufacturer: Gigabyte Technology Co., Ltd.
Product Name: X570 AORUS MASTER
System Version: -CF

ADDITIONAL INFORMATION

Comment 1 timon2201 2025-10-31 12:45:19 UTC

for the overlay planes i did everything as described in https://invent.kde.org/plasma/kwin/-/merge_requests/7795 for the testing part. So disabling the rounded corner stuff and so on.

Comment 2 Zamundaaa 2025-10-31 16:09:03 UTC

(In reply to timon2201 from comment #0)
> But what i can say is that when i downgrade kwin from 6.5.1 to 6.4.91 then
> everything is very smooth and the inconsistencies are gone. I didn't try it
> yet with kwin 6.5.1 and KWIN_USE_OVERLAYS=0 .
Do test that, this is almost certainly https://gitlab.freedesktop.org/drm/amd/-/issues/4358

I can't explain why it would be any different in 6.4.91 though, there weren't any significant overlay related changes since then

Comment 3 timon2201 2025-10-31 22:15:07 UTC

yes, it seems to be gone when i play with KWIN_USE_OVERLAYS not set at all and kwin 6.5.1

Comment 4 Bug Janitor Service 2025-11-15 03:47:45 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.

Thank you for helping us make KDE software even better for everyone!

Comment 5 Bug Janitor Service 2025-11-30 03:46:03 UTC

🐛🧹 This bug has been in NEEDSINFO status with no change for at least 30 days. Closing as RESOLVED WORKSFORME.

Comment 6 Zamundaaa 2025-12-05 16:54:30 UTC

FWIW commenting on the upstream bug report might help prioritize it a little bit. If it's reproducible on more than just my system, it should make things easier :)