gnome-shell uses 30-100% CPU

[Tomasz]

gnome-shell uses 30-100% CPU
After investigation problem is because a lot of recvmsg:

strace:
---------
recvmsg(16, {msg_namelen=0}, 0) = -1 EAGAIN (Zasoby chwilowo niedostępne)
recvmsg(16, {msg_namelen=0}, 0) = -1 EAGAIN (Zasoby chwilowo niedostępne)
recvmsg(6, {msg_namelen=0}, 0) = -1 EAGAIN (Zasoby chwilowo niedostępne)
recvmsg(6, {msg_namelen=0}, 0) = -1 EAGAIN (Zasoby chwilowo niedostępne)
recvmsg(16, {msg_namelen=0}, 0) = -1 EAGAIN (Zasoby chwilowo niedostępne)
recvmsg(16, {msg_namelen=0}, 0) = -1 EAGAIN (Zasoby chwilowo niedostępne)
recvmsg(6, {msg_namelen=0}, 0) = -1 EAGAIN (Zasoby chwilowo niedostępne)
recvmsg(6, {msg_namelen=0}, 0) = -1 EAGAIN (Zasoby chwilowo niedostępne)
----------

lsof output:
gnome-she 14772 xxx 6u unix 0x0000000000000000 0t0 133056 type=STREAM
gnome-she 14772 xxx 16u unix 0x0000000000000000 0t0 133062 type=STREAM

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: gnome-shell 42.4-0ubuntu0.22.04.1
ProcVersionSignature: Ubuntu 5.15.0-50.56-generic 5.15.60
Uname: Linux 5.15.0-50-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu82.1
Architecture: amd64
CasperMD5CheckResult: pass
CurrentDesktop: ubuntu:GNOME
Date: Sun Oct 16 18:50:20 2022
DisplayManager: gdm3
EcryptfsInUse: Yes
InstallationDate: Installed on 2022-09-29 (17 days ago)
InstallationMedia: Ubuntu 22.04.1 LTS "Jammy Jellyfish" - Release amd64 (20220809.1)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=pl_PL.UTF-8
 SHELL=/bin/bash
RelatedPackageVersions: mutter-common 42.2-0ubuntu1
SourcePackage: gnome-shell
UpgradeStatus: No upgrade log present (probably fresh install)

[Daniel van Vugt (vanvugt)]

It's unlikely even busy system calls like that are the real issue here.

Please start by disabling all your shell extensions and tell us if that improves the situation.

Please also try deleting local unsupported extensions:

  cd ~/.local/share/gnome-shell/
  rm -rf extensions

and then log in again.

[Daniel van Vugt (vanvugt)]

Also note there is a memory leak in the graphics driver affecting your particular GPU: bug 1972977. So we should check to see if that fixes it when the fix is available for 22.04.

[Tomasz (rejli)]

Unfortunately disabling extenstion doesn't resolve the problem.
Do you have any idea what to do next?

[Daniel van Vugt (vanvugt)]

1. Disable extensions and log in again.

2. Delete extensions:

   cd ~/.local/share/gnome-shell/
   rm -rf extensions

   and log in again.

3. Close all apps except for a Terminal window and run 'top'. Is high CPU still occurring?

4. Look at the screen and tell us what, if any, part is changing regularly (indicators/windows).

[Launchpad Janitor (janitor)]

[Expired for gnome-shell (Ubuntu) because there has been no activity for 60 days.]