Bug 376676

Summary: thumbnail.so causes high CPU load
Product: [Frameworks and Libraries] kio-extras Reporter: Peter Ullinger <peter.ullinger>
Component: Thumbnails and previewsAssignee: Plasma Bugs List <plasma-bugs>
Status: REPORTED ---    
Severity: minor CC: bhush94, d_debnath, jareyoh415, loveisgrief, michele.mazza, nate, plasma-bugs
Priority: NOR    
Version: 5.9.2   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed In:
Attachments: Excerpt from Ksys informations about thumbnail.so during the high load.

Description Peter Ullinger 2017-02-19 15:35:25 UTC
Created attachment 104114 [details]
Excerpt from Ksys informations about thumbnail.so during the high load.

thumbnail.so causes high CPU load every time it has to work on a formaly uncrawled folder.

Plasma Version: 5.9.2
Framework Version: 5.31.0
Qt Version: 5.8.0
Distro: Manjaro 64 Bit
Comment 1 David Edmundson 2017-02-19 23:50:06 UTC
Attaching a file of memory allocations tells us nothing about the CPU load.

If you want to reopen this bug, I need:

 - the name of the process that's using a lot of CPU. 

 - Was something meant to be showing an uncrawled folder? If so, what part makes a bug.

 - Ideally, a callgrind log.
Comment 2 Peter Ullinger 2017-02-20 05:22:26 UTC
- The name of the process causing the high CPU load is thumbnail.so according to htop and ksysguard.
- The process is started every time I browse a folder with Dolphin and switch on the preview. thumbnail.so will then use 100% of one CPU core until I kill it, even if this folder has only three PDFs or two videos in it and those are shown after a split of a second.
- Sorry, but what is a callgrind log, and where do I find thumbnail.so's one? 

Htops infos: https://goo.gl/photos/ZaQrtizfXu9rkqJH6
Comment 3 D. Debnath 2020-01-28 05:44:13 UTC
I confirm this bug.

This happened to me when Dolphin had a folder open where there is a file that's being modified continuously, in my case I was downloading a file using aria2c.
Comment 4 D. Debnath 2020-01-28 05:45:10 UTC
There is a reddit thread about it from about a year ago: https://www.reddit.com/r/kde/comments/a56xwb/thumbnailso_100_cpu_after_upgrade_in_debian/
Comment 5 Jon 2020-05-25 13:43:50 UTC
This bug is still relevant!

Manifests itself, when Dolphin had a folder open where there is a file that's being modified continuously.
Comment 6 Lo 2020-06-01 14:36:10 UTC
Can confirm on OpenSuse Tumbleweed. Trying to generate thumbnails on a read-only drive.