SUMMARY For example, just hover over something in the left panel and wait for the highlight to activate, it takes multiple seconds (~7). Also the entire app refreshes at ~1 fps or less, doesn't maximize, and stops responding (greys out) often. Plasma 5.20.2, Qt 5.15.1, KF 5.75, Wayland only
I can confirm this on Wayland as well. Operating System: Arch Linux KDE Plasma Version: 5.20.2 KDE Frameworks Version: 5.75.0 Qt Version: 5.15.1 Kernel Version: 5.9.6-arch1-1
What kind of GPU are you running on? We do nothing special that should slow things down on Wayland, but the charts are all rendered by the GPU which might cause slowdowns in some cases. Also, have you checked whether the same happens on X?
I have a AMD Vega 8 GPU inside a Ryzen 5 3550H. This issue is not present in X.org session, only in Wayland.
I also tested this on a different laptop with Manjaro and I got the same behavior. The other system has a Intel Haswell GPU, so it's not something like this: https://bugs.kde.org/show_bug.cgi?id=424398
Alright thank you, I am also running on a Vega 8. Thanks for verifying that it is only on Wayland, will need to investigate what's going on there.
The BusyIndicator is the main cause for excessive CPU use and slowness here. Making that invisible improves it significantly, but it's still not responsive enough. I can't narrow it down to any other specific component after that though, it seems to be spread out over the entire tree. e.g. making the the pie charts invisible helps a bit, hiding the process table helps a bit, etc.
Does anyone still have this issue? I don't since 5.21 Beta.
Can confirm. The issue is no longer present on Wayland (Plasma 5.21 Beta).
Great. Then I'm closing this.