gnome-shell freezing with "Attempting to run a JS callback during garbage collection." messages

[Kai Groner]

This happened soon after logging in. The entire desktop (mouse cursor included) would freeze for maybe 30 seconds at a time. The activities screen seemed to trigger it. The dock appeared empty.

After a few minutes of this I rebooted and things seem to be alright now.

Relevant log messages start on May 5 at 11:10 AM US/Eastern time.

Similar messages appear on March 31st. I don't recall whether I experienced similar freezing behavior at that time.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: gnome-shell 3.36.1-5ubuntu1
ProcVersionSignature: Ubuntu 5.4.0-28.32-generic 5.4.30
Uname: Linux 5.4.0-28-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.20.11-0ubuntu27
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Tue May 5 11:22:41 2020
DisplayManager: gdm3
InstallationDate: Installed on 2019-06-18 (322 days ago)
InstallationMedia: Ubuntu 19.04 "Disco Dingo" - Release amd64 (20190416)
ProcEnviron:
 TERM=tmux-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
RelatedPackageVersions: mutter-common 3.36.1-3ubuntu3
SourcePackage: gnome-shell
UpgradeStatus: Upgraded to focal on 2020-04-21 (13 days ago)

[Daniel van Vugt (vanvugt)]

That log message is actually pretty common and probably not related to any freezes. To confirm this please open a Terminal window and start monitoring the log:

  journalctl -f

Now please check to see if the messages correlate closely with the freezes. And tell us if any of them appear when the freeze is *not* happening.

[Daniel van Vugt (vanvugt)]

Please also run 'top' or 'ps auxw' and tell us how much memory the gnome-shell processes are using.

[Kai Groner (kai-gronr)]

In logs I have going back 6 months the errors "Attempting to run a JS callback during garbage collection." and "The offending callback was ..." only appear on one other date.

There is a similar message "Attempting to call back into JSAPI during the sweeping phase of GC." that appears more frequently.

I think it will be hard to get good timing data when the console is freezing and unresponsive and I'm not sure when the issue might re-occur.

I'm attaching the log from this session, as well as the log from my current session for comparison.

[Kai Groner (kai-gronr)]

From top, just now (gnome-shell has not been freezing during this session):

    PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
   3885 kai 20 0 8342772 602120 331580 R 12.9 1.8 101:26.43 gnome-shell

When I enter and leave the activities screen, CPU time spikes to about 30%. At idle it runs between 3% and 13%.

Cumulative CPU time is over 8-10h.

I don't have any record of the resource usage when it was freezing, but I will try to grab that if it happens again. This probably wasn't a low memory situation as the machine had just booted and I had wasn't able to run anything more than a terminal before I gave up and rebooted.

[Daniel van Vugt (vanvugt)]

Please:

1. Attach only the portion of the log relating to the command in comment #2 - while the freeze is occurring. You will need to start the command, wait till the freeze happens, and then send us the most recent messages only.

2. Provide 'top' output from a fresh session immediately after a freeze occurs. Because as you said; "This happened soon after logging in".

3. Run 'gnome-shell-extension-prefs' and disable 'Ubuntu AppIndicators'. Leave it disabled and tell us if that avoids the problem.

4. Tell us if 'gnome-shell-extension-prefs' shows any other extensions enabled.

5. Run:

   lspci -k > lspcik.txt

   and send us the resulting file.

[Kai Groner (kai-gronr)]

The full log is the best I can offer unless I figure out how to reproduce this (it hasn't even re-occurred randomly). If you skip the first 50 lines and ignore the libinput errors, it's entirely errors produced during or immediately after a freeze.

gnome-shell-extension-prefs shows the following enabled:
- Desktop Icons
- Ubuntu AppIndicators
- Ubuntu Dock

I don't know how to reproduce this problem, so I can't meaningfully test disabling the Ubuntu AppIndicators extension.

[Launchpad Janitor (janitor)]

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