I upgraded to 12.04 Tuesday (1 May) and as of 3 May the GUI has hung 4-5 times:

  1. the clock stops moving
  2. the mouse cursor is responsive, but nothing happens when I click
  3. I can ssh to the machine

I have tried killing various processes, but have not found which to kill to make any difference, so I end up rebooting.

I applied an update from yesterday (which was a new kernel) and that has not helped.

Linux berlioz 3.2.0-24-generic #38-Ubuntu SMP Tue May 1 16:18:50 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

Machine: Intel 2 Duo X6800, Asus P5B Deluxe, Graphics: NVidia GeForce 7300GS (256MB)

I'm not using Unity (gnome3 instead), I did not install compiz, but I don't know if it's installed.

Obviously this makes it pretty much unusable. What can I do to capture some information so that someone can tell what's going on and I can get a fix? Or is there any process I can kill that will allow me to avoid a reboot? If this cannot be fixed soon, is there a way to move back to the previous working release?


I followed the suggestions in the answer to this question: https://askubuntu.com/questions/130387/stuck-at-login-screen

And now my system will not boot. The last line it gives is:

  • Starting TiMidity++ ALSA midi emulation [OK]

(this happens consistently upon a full boot -- I suppose I need to see what's happening next in the boot, or perhaps remove the TiMidity thing in recovery mode somehow)


I was able to boot in recovery mode after changing the gdm to use lightdm, I can not boot normally. I will try to see what's happening in dmesg if the hang happens again.


dmesg output at the time of the hang:



I have filed this bug report:



Another data point, this seems to be related to the multiload indicator that shows multiple bar-graphs in the Gnome panel. I switched to this type of system indicator when upgrading to 12.04 (I previously used a different one that showed only a single bar graph, but I could not find that one again after I updated)

Here is a link to the multiload-indicator that seems to be causing the problems:


Note that I use this in the gnome-panel (below) rather than that indicator bar that it at the top.

Since I have disabled this multiload-indicator, the problem has not happened once.

  • Are you using unity? Have you got compiz enabled? Please do add these informations to the question. :) May 3, 2012 at 14:28
  • Edited to answer the questions May 3, 2012 at 14:37
  • Did you use Google Earth by any chance? Any other OpenGL application? If you can ssh into the system when it's hanging, can you run dmesg and look for anything suspicious? Tell us more about your hardware (CPU, graphics).
    – htorque
    May 3, 2012 at 14:38
  • I did not use Google Earth, nor any other OpenGL application (that I know of), it happened once when I was just hitting the tab key in a terminal window to get completion, and at another similar time. May 3, 2012 at 14:47
  • Edited again to add processor/graphics information and problems I'm having on rebooting. May 3, 2012 at 14:57

2 Answers 2


This problem seems to be caused by the open source nouveau driver. I switched to the Nvidia driver and the problem went away. Also, my display seemed to get a little clearer.

  • Unfortunately this didn't solve the issue for me. Sep 20, 2021 at 15:41

I've found that killing gnome-shell works for me in similar circumstances (either from ssh, or using ctl-alt-F1 to bring up a console prompt):

pkill -hup gnome-shell

However, that's a fix for the symptom, not a way of resolving the root cause.

  • It was not responsive to ctl-alt-F1 while hanging, but thanks for the suggestion. May 3, 2012 at 14:44
  • I sshed and killed the gnome-shell which had no effect, I killed all gnome processes and that made the monitor go blank of course, but I could not log in again or get any response from the GUI. May 3, 2012 at 20:23

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .