Discussion in this thread with @cscs prompted me to investigate the cause of plasmashell’s excessive GPU memory consumption under Wayland. Using this command I could see my GPU’s memory consumption near real-time:
nvidia-smi -l 1
I was seeing the GPU memory jump-increase roughly 2 times a minute, and quickly realised it was happening when my slideshow wallpapers cycled every minute! It’s per-display too, so additional displays multiply the issue. Over the course of a day, that adds up! I changed the cycle interval to 2 seconds and sure enough, GPU memory was getting chewed up.
Investigating the issue online revealed long standing memory issues under Plasma with slideshow wallpapers, dating back years, so I’m not pinning my hopes on a fix at the moment. For now the options are:
- Stop using slideshow wallpapers, or reduce the cycle interval so the issue is slower.
- As needed, restart
plasmashell, which will free up the GPU memory:
plasmashell --restart &