Caja 100% CPU usage

Ubuntu MATE 20.04, fresh install.

Every couple of days, Caja (apparently randomly) uses over 100% CPU usage and is painfully slow to respond to input. If I open the menu "edit - preferences - preview" and set either one of 'show text in icons' or 'show thumbnails' to "never", CPU usage returns to normal and Caja is again responsive. I set the changed option back to "local files only" and all remains good for a few days.

Has anybody else got issues with Caja using 100% CPU usage? If so, can you try changing the setting I mention and see if that also works for you?

I want to report a bug but would value someone confirming the same.

UPDATE. I have a very similar problems on Ubuntu proper also, Nautilus uses 100% CPU on login and is simply unresponsive.

The common factor is that my standard home subfolders, Pictures, Videos, Downloads, Documents, Templates, Public (but not the actual home folder itself) are links to folders on a different drive.

UPDATE 2 : I have restored my normal home folders (Pictures, Downloads etc), and created links inside those folders to the folders on the other drive. The issue has gone away, no more 100% CPU usage.

I will report a bug.

Ubuntu 22.04.4 LTS
Mate Desktop
all updates installed (except Ubuntu-Pro)
When I log in, caja is consuming about 33% cpu time on about 3 virtual cores (i.e. 1 virtual core completely), at the same time reading 1 MiB/s .. 4 MiB/s and writing 250KiB/s .. 1MiB/s from/to disk.
The only reason this doesn't hinder me is because I have enough cores.
The issue persists for hours.
The process is obviously stopped when I log out and is restarted when I log in again.
The issue seems to have something to do with PDF-files (of which I have many).
The trigger seems to be the replacement of one or more existing PDF-files.

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And right, Setting caja: Edit/Preferences/Preview/"Show thumbnails" to never, stops the issue.


Welcome @norbert to the community!

Nice to be welcomed!

I'll refine my post from 2024/03/24:
The problem obviously affects graphic files (photos), i.e. JPG or PNG files, not PDF files, but indeed PDF files that contain photos.
The massive CPU and storage usage is triggered by the replacement of a single of the denoted files.
For me, storing about 6500 of such files, it lasts days.
Of course, setting caja: Edit/Preferences/Preview/"Show thumbnails" to "never" ends the process, but then I can no longer see the 40 thumbnails on the desktop that are important to me.

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Just found: seemingly exactly the same problem is already reported more than 5 years ago, and (at least for the reporter) started at that time:

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I had the same problem with an Intel machine, whose graphics driver was not compatible with the version of Ubuntu. Try changing the graphics driver or updating it

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I am already running the nvidia driver recommended for my ubuntu, i.e. 470.239.06. And it doesn't look like a driver problem at all. Remember: Overwriting a single graphics file probably triggers renewing the complete set of stored thumbnails.