Arch Linux

kaushikgn

Member

Registered: 2020-04-12

Posts: 52

Very high cpu uasgae of plasma on Wayland

Hi
When istart a KDE wayland session i get a black screen and the system freezes when lightdm greeter tries to handover to plasma desktop.My machine details are 5.6.11-arch1-1,
pacman -Qs nvidia
local/libvdpau 1.3-1
    Nvidia VDPAU library
local/nvidia 440.82-12
    NVIDIA drivers for linux
local/nvidia-utils 440.82-1
    NVIDIA drivers utilities
plasma is the latest version from Arch linux repo.
kwin wayland is constantly at 80% or even more cpu usage.This is without any window open except the odd terminator and ksysguard resource mon.
even if one moves the mouse or clicks inside a winow without performing any action (like click,close.open etc.) the cpu spikes to 90.
Things are so bad that its pretty much unusable and tthings like lsof , pstat takes too long to return back any data.
Dont know where to start debugging.

Last edited by kaushikgn (2020-05-10 16:03:09)

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 25,381

Re: Very high cpu uasgae of plasma on Wayland

You need to enable modesetting for this to have any chance of working. Add

nvidia-drm.modeset=1

to your kernel parameters. Also xorg logs are pretty useless in this context, post a journal log

sudo journalctl -b

Also note that all of this is still quite experimental/work in progress and only plasma has any sensible support as far as I know and even there it's quite in flux.

kaushikgn

Member

Registered: 2020-04-12

Posts: 52

Re: Very high cpu uasgae of plasma on Wayland

It worked with modeset=1 but the kwin is spiking up cpu usage to 80% and above.At the mo, cant upload journal log to pastebin.
I have bin looking for any such things but nothing reakky helped.Disabling all effects does not either.Thanks v1del

It happens only when using wayland.X11 is fine.Is there any resolution for this or just give up wayland?!

Last edited by kaushikgn (2020-05-08 14:09:32)

twelveeighty

Member

Registered: 2011-09-04

Posts: 1,456

Re: Very high cpu uasgae of plasma on Wayland

As V1del said: "all of this is still quite experimental/work in progress". But nobody here is going to tell you to give up on Wayland, if that's what you want to do? That choice is yours to make.

If you want to continue troubleshooting, switch back to modesetting and change your post title to "High CPU usage with KDE on Wayland" or something similar, since getting it to start but with high CPU usage is much, much further ahead than getting a crash/black screen without modesetting.

Did you read: https://community.kde.org/Plasma/Wayland_Showstoppers ?