Bug 470427 - "kwin_wayland" overloading CPU getting unusable desktop
Summary: "kwin_wayland" overloading CPU getting unusable desktop
Status: RESOLVED NOT A BUG
Alias: None
Product: kwin
Classification: Plasma
Component: wayland-generic (show other bugs)
Version: 5.27.5
Platform: openSUSE Linux
: NOR grave
Target Milestone: ---
Assignee: KWin default assignee
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2023-05-29 19:40 UTC by Rafael Linux User
Modified: 2023-06-01 12:13 UTC (History)
2 users (show)

See Also:
Latest Commit:
Version Fixed In:
Sentry Crash Report:


Attachments
perf.data view (74.94 KB, image/webp)
2023-05-29 19:40 UTC, Rafael Linux User
Details

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Description Rafael Linux User 2023-05-29 19:40:32 UTC
Created attachment 159328 [details]
perf.data view

SUMMARY
Enabling Wayland session in Plasma I got an unusable desktop. 1 CPU  core is used at 100%). All is so slow that moving mouse takes 3 to 4 seconds each time, jumping from one place to next, like if FPS dropped all over desktop. 

"kwin_wayland" is the process eating CPU. These are the sub-threads involved (I got from perf.data):
- kms_swrast_dri.so (repeated x 5 times) at 99.3% CPU
- libc.so.6 (repeated x 2 times) at  99.3% CPU

STEPS TO REPRODUCE
1. Select Wayland before authenticate user
2. Authenticate user
3. Desktop works like 1/10 of normal speed

OBSERVED RESULT
If I switch to Ctrl+Alt+F1 and come back to desktop, I only have mouse pointer over a black desktop. No way to click nothing, cause there is nothing to click in, only a black background and my mouse pointer.

EXPECTED RESULT
To work like with X Org Session

SOFTWARE/OS VERSIONS
Operating System: openSUSE Tumbleweed 20230527
KDE Plasma Version: 5.27.5
KDE Frameworks Version: 5.106.0
Qt Version: 5.15.9
Kernel Version: 6.3.2-1-default (64-bit)
Graphics Platform: Wayland
Processors: 4 × Intel® Core™ i5-6600K CPU @ 3.50GHz
Memory: 31.3 GiB of RAM
Graphics Processor: NVIDIA GeForce GTX 1050 Ti/PCIe/SSE2

ADDITIONAL INFORMATION
Nvidia original repository drivers installed. No issues at all in X Window session.
Comment 1 David Edmundson 2023-06-01 11:15:15 UTC
swrast means we're using software rendering which is a fallback.
This is a setup issue.
Comment 2 Rafael Linux User 2023-06-01 12:13:02 UTC
In fact, I compared two PCs with same S.O. but distinct Nvidia graphics cards. In one Wayland works but not in the other. I compared info about "Windows manager" and found two differences:
1 -  OpenGL platform interface is EGL in working Wayland PC, GLX in the other one
2 - QT5 AND QT6 are installed in working Wayland PC, only QT5 is in the other one

So, is it neccesary QT6 to get Wayland work??

Thank you for your comment