Bug 511935

Summary:	Plasma 6.5 abnormal plasmashell CPU usage with slideshow wallpapers
Product:	[Plasma] plasmashell	Reporter:	Andrea Tonello <andrea.tonello>
Component:	Wallpaper images	Assignee:	Plasma Bugs List <plasma-bugs-null>
Status:	NEEDSINFO WAITINGFORINFO
Severity:	major	CC:	nate, wolf
Priority:	NOR
Version First Reported In:	6.5.0
Target Milestone:	1.0
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Andrea Tonello 2025-11-10 23:01:05 UTC

SUMMARY
Very high CPU usage for plasmashell (12-18%) when selecting slideshow wallpaper with the ordered alphabetical option (A-Z, Z-A). The Order by Date and Random options do not seem to cause issues.
It is worth noting that the problem seems to worsen as the number of source folders for images increases (in my case, i noticed 8-12% with the default usr/share/wallpapers, and 12-18% with another custom folder added).

STEPS TO REPRODUCE
1. Set wallpaper option to slideshow, with alphabetical order (A-Z or Z-A)
2. Open a resource monitor. I used Plasma's system monitor
3. plasmashell CPU usage is reported as 12-18%

OBSERVED RESULT
Abnormal plasmashell CPU usage, around 12-18%

EXPECTED RESULT
Should be around 1-3%

SOFTWARE/OS VERSIONS
Fedora Linux 43 6.17.7-300.fc43.x86_64
KDE Plasma Version:  6.5.2
KDE Frameworks Version:  6.19.0
Qt Version: 6.10.0

ADDITIONAL INFORMATION
I'm 99% sure this wasn't the case in 6.4, because I first observed the behavior on my laptop with 6.5. Then I went to my desktop with 6.4, where i confirmed the behavior was not present. I then installed 6.5 on my desktop too, and the behavior did appear with 6.5 installed.

Comment 1 Nate Graham 2025-12-12 21:28:53 UTC

A few questions:
1. What update interval is the slideshow using?
2. What kind of GPU does the system have?
3. What's the resolution and scale factor of the screen (or screens, if this system has more than one)?
4. When you're reproducing the problem with only /usr/share/wallpapers, are there only Plasma wallpapers in there? Or are there other wallpapers from other sources?

Comment 2 Bug Janitor Service 2025-12-27 03:46:35 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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