Wireplumber 100% cpu while changing volume slider in Kde Plasma
Originally reported downstream to kde here but it seems to be an upstream issue with Wireplumber
My volume sliders freeze up if i'm too quickly dragging them to change volume. This only happens if i drag them with the mouse, not while changing volume via keyboard or via the scrollwheel. I've noticed wireplumber cpu usage goes to 100% on one core. If i downgrade Wireplumber to 0.4.17 it gets better but still a bit janky. Happens on both x11 and Wayland.
STEPS TO REPRODUCE
- have wireplumber ver 0.5.6 running
- change system volume via any slider
OBSERVED RESULT
Plasma freezes for a while and wireplumber can't keep up with commands sent
EXPECTED RESULT
System is smooth
Someone suggested this is a regression in upstream:
Yeah I am not sure we can do anything here. Looks like a wireplumber/pipewire regression compared to pulseaudio. We simply forward the GUI events (depending on size, some 500 events if you move the bar from start to finish) and what appears to happen it that the daemon cannot keep up with the amount of changes and so the actual update of the volume is severely delayed (which makes it look like the slider is stuck - it's really just waiting for the daemon to report the new volume). For good measure I've tried to cancel operations as new volumes get set, but that doesn't help either. So, we don't really have any way to deal with this on the client side I think. Please file a bug upstream.
Apologies if this was filed under the wrong category or project.