libQt5Core5 5.9.1 causes memory leak & Plasma crash

Since upgrading from libQt5Core5 5.9.0 to 5.9.1, I experience two issues with plasmashell, which seem to be caused by the same core problem.

The first is that the desktop causes massive memory usage. In over an hour, my system goes from using 2GB of memory (after booting and opening my applications) to approximately 8GB! However this memory is not attributed to any one process; It seems to be disk cache memory, which is further indicated by the fact that issuing the command “echo 3 > /proc/sys/vm/drop_caches” causes some of it to be freed up (not all).

The second issue is that every few hours, plasmashell will crash and restart. I use an image slideshow wallpaper, and before the crash it always becomes black instead of an image… plasmashell then dies immediately after I attempt to click anything on the desktop.

Showing a screenshot of the desktop as it becomes broken. It shows both the Media Frame widget and slideshow wallpaper being replaced by a black color, whereas normally they should contain images… it’s at this point that clicking on things causes Plasma to crash and restart. The only edits include me blurring the contents of a plasmoid, and adding the red text and arrows to better indicate what happens.

For your investigation,

I wrote up a “How To” for understanding how to use the Free tool.

Included is an improved command for clearing your memory buffers and cache, and suggest a couple other tools which can further analyze your memory usage.


Thanks for the info! And here is the output of the “free” command, after plasmashell has leaked its fair amount of memory:

              total        used        free      shared  buff/cache   available
Mem:       24685912     9939572     5941788      115812     8804552    14230988
Swap:       8191996           0     8191996

A heads up: I believe someone added a patch to the upstream bug, which users have tested and said fixes the memory leaks (hopefully the blackness too). Hoping the openSUSE crew is staying tuned to that, so this patch can be added to Tumbleweed as soon as it’s available.