Bug 459692

Summary:	[Wayland] kwin_wayland 100% cpu, system lagging, intel + nvidia optimus with external monitors
Product:	[Plasma] kwin	Reporter:	Jeannie Stevenson <jeanniestevenson>
Component:	platform-drm	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED DUPLICATE
Severity:	major	CC:	nate, xaver.hugl
Priority:	NOR
Version:	5.25.5
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed In:

Description Jeannie Stevenson 2022-09-26 09:49:20 UTC

SUMMARY
Starting a NVIDIA Optimus machine with a monitor plugged into an output controlled by the NVIDIA card on wayland with kwin causes kwin_wayland to hog CPU on a single core, leading to very poor graphical performance.

Works fine when no external monitors are plugged in. I've attached my kwin_wayland log below.
https://pastebin.com/uJkPmC4f is the kwin_wayland log with monitors plugged in on boot.
https://pastebin.com/WSz7BXXs is the kwin_wayland log without monitors plugged in, where everything works fine.

STEPS TO REPRODUCE
1.  Connect Optimus Laptop with NVIDIA outputs to external monitor
2. Start KDE 

OBSERVED RESULT


EXPECTED RESULT
Low CPU usage and responsive desktop

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 5.25.5
KDE Frameworks Version: 5.98.0
Qt Version: 5.15.6

Comment 1 Zamundaaa 2022-09-26 21:31:47 UTC


*** This bug has been marked as a duplicate of bug 452219 ***