kwin_x11 using a lot of GPU for no obvious reasons

Help
1

Hi everyone

I’m using Kubuntu 22.04 with latest Nvidia drivers, laptop is Legion 5 (Ryzen 7 and Nvidia GTX 1650Ti).

For some reason kwin_x11 is using GPU all the time and this makes GPU temperature around 50C which makes the fans run all the time.I tried with kwin_x11 --replace and it helps for a few minutes, but then again the usage goes back to around 30%.

I disabled blur and transparency effects.

This is the output from nvidia-smi pmon -c 1:

# gpu         pid  type    sm    mem    enc    dec    command
# Idx           #   C/G     %      %      %      %    name
    0       8154     G      -      -      -      -    Xorg           
    0      11300     G      -      -      -      -    plasmashell    
    0      11390     G      -      -      -      -    jetbrains-toolb
    0      11717     G      -      -      -      -    common -       
    0      16790     G      -      -      -      -    firefox        
    0      17355     G      -      -      -      -    chrome --type=g
    0      77627     G      -      -      -      -    krunner        
    0      77705     G     42      9      -      -    kwin_x11

Is there anything else I can disable to lower the GPU usage.

2

I am having the same problem in Manjaro KDE. The process kwin_x11 (kwin_x11 --replace) is using too much GPU, it happens just after booting the system, but after a while the process goes back to normal and not using too much GPU.
I don’t know if this is a problem or it’s the default behavior. But if it continues like that, then it’s not an issue, since it uses higher GPU just a few minutes after booting, then goes to normal.

3

I noticed that the kwin_x11 process does not go back to normal on it’s own, i have monitored it for like 10 minutes directly after booting and it kept using high GPU. Only when i started firefox, that it went back to normal GPU usage, and when i closed Firefox, it kept working as normal. Weird.