Plasma5 and multi session single seat, memory leak...

07 February 2023, 11:22:59

Not user there are other users out there who has a scenario where there are more than one user using a computer, each logged in to their own session on a machine with just one seat.

We using quite plain desktops, display of ~/Desktop, clock, fixed wallpaper. It seems as soon as a session isn't the active one it starts after a while to just consume more and more memory. There been instances where one plasmashell takes up 58GB of RAM (and I have only 64GB installed on the desktop), sometimes this triggers kswapd to start to do things (no swap configured on system and swappiness is set to 0) and then the desktop is completely unusable and the only solution is to find a ssh connection that is already connected to the machine and you are root user, so that you can run "killall -9 plasmashell" or you have to press the reset button.

Upstream this seems to be unprioritized issue.

Anyone have any suggestions on workarounds? Sure we can change to another desktop environment, but they don't really offer us a CSD free window manager that can disable all hotkeys for a specific window (it's quite good when using looking-glass to the virtual machine).

I have tried to use another window manager, like plasma5/ctwm, it only makes things to go slightly slower, but plasmashell will eat the memory in the end. Lumina/kwin works kind of, but it's quite limited in features and pavucontrol-qt don't work. Lxqt has it's issues too when not using it with openbox. Cutefish and deeping both goes with CSD and the ugly issue that title bar is of different height depending on content and even without they are larger than what default kwin title bar is.

Re: Plasma5 and multi session single seat, memory leak...

Reply #1 – 07 February 2023, 15:02:15

You can do the other way round and use KWin but on the LXQt desktop.
For advanced features if KWin doesn't safisfy try icewm

Re: Plasma5 and multi session single seat, memory leak...

Reply #2 – 07 February 2023, 15:20:20

I get a really unresponsive desktop (input is kind of delayed 2 minutes) if I try to run kwin_x11 as window manager for LXQt, after testing some of my icons has changed look. LXQt do work if using say ctrwm as window manager.