Bug 510240 - High cpu usage (10%) which goes away when taskbar auto hide is off
Summary: High cpu usage (10%) which goes away when taskbar auto hide is off
Status: RESOLVED DUPLICATE of bug 477855
Alias: None
Product: kwin
Classification: Plasma
Component: effects-window-management (other bugs)
Version First Reported In: 6.4.5
Platform: Arch Linux Linux
: NOR normal
Target Milestone: ---
Assignee: KWin default assignee
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2025-10-04 20:51 UTC by fluffball3
Modified: 2025-10-07 13:21 UTC (History)
2 users (show)

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


Attachments
errors from journalctl (9.24 KB, text/plain)
2025-10-04 20:51 UTC, fluffball3
Details
support info (6.06 KB, text/plain)
2025-10-04 21:02 UTC, fluffball3
Details

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Description fluffball3 2025-10-04 20:51:57 UTC
Created attachment 185519 [details]
errors from journalctl

SUMMARY

I've been very confused by htop readings of 10% or more cpu utilization even when idle for kwin_wayland process.... Tried many stuff but in the end it seems like bringing up the taskbar from auto hide mode lets cpu go back to 1% or 2% usage. Attached journalctl logs which mention some other errors as well.

STEPS TO REPRODUCE
1. Start something for example floorp
2. Ensure cpu goes above 10% or something
3. Close it after some time

OBSERVED RESULT

CPU usage doesn't go below 10% and sometimes more unless taskbar is activated or kwin_wayland --replace is run.
CPU usage drops immediately as well

EXPECTED RESULT

CPU usage should be lower when idle 

SOFTWARE/OS VERSIONS

Operating System: Arch Linux
KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.18.0
Qt Version: 6.9.2
Kernel Version: 6.17.0-4-cachyos (64-bit)
Graphics Platform: Wayland
Processors: 12 × 12th Gen Intel® Core™ i5-12450H
Memory: 16 GiB of RAM (15.3 GiB usable)
Graphics Processor 1: Intel® Graphics
Graphics Processor 2: NVIDIA GeForce RTX 4060 Laptop GPU

ADDITIONAL INFORMATION

I have been using cachyos repo packages installed while pacstrapping (its a recent re-installation).
Installed mesa-tkg-git and also tried Intel Xe driver both high cpu usage issue and the other errors still persist.
Comment 1 fluffball3 2025-10-04 21:02:33 UTC
Created attachment 185520 [details]
support info

support info
Comment 2 David Redondo 2025-10-06 13:15:13 UTC
I think this is 477855

*** This bug has been marked as a duplicate of bug 477855 ***
Comment 3 fluffball3 2025-10-06 18:59:06 UTC
Ok so I guess I'll wait for update which seems to have patch for this. Thanks for looking into this.