/usr/share/ibus/ui/gtk/main.py blocks at 100% when applications are minimised

[Urop]

When I minimise applications such as thunderbird and firefox, they frequently sit in the unity launcher with the application icon and arrow flickering and my computer becomes frozen for up to 5 mins. Checking top shows me that compiz and a python script are both having a fight with python at 100%. Investigating further shows me that the python script causing the problem is /usr/share/ibus/ui/gtk/main.py

This is most annoying, and I have now encountered the same problem on two separate computers running Quantal with different graphics cards. I have ibus and ibus-anthy installed on both of them.

In case it is useful, I found an old thread reporting a similar problem in 2010 with Ubuntu 10.10 [1]. Then the solution appears to have been to upgrade to the latest version of ibus (1.3 at the time). I don't know if upgrading to the latest development release would solve the problem. If a launchpad PPA for a bleeding edge version of ibus was available for Quantal, I'd be happy to test it.

Cheers.

[1] http://mypace75.blog92.fc2.com/blog-entry-767.html

[Urop (urop)]

I've attached a screenshot of top showing thunderbird and the ibus python script hamming a couple of processors in tandem, with the flashing unity panel and ibus-daemon not far behind. It's most annoying and, when I have my virtual machine on too, my can't cope any longer and freezes!

Note that I also have an encrypted home directory, so this could be related to bug #927515 too. Either way, I would be grateful if someone could investigate.

[Urop (urop)]

I've just upgraded to Raring and noticed that the problem appears to be even worse now. It happens whenever I try to close or minimise Thunderbird. If I go to the ibus keyboard icon in the system tray and click on it, the drop down menu is in a state of constant flickering.

I did some experiments and noticed that killing the usr/share/ibus/ui/gtk/main.py python script process doesn't help. Thunderbird keeps using 100% cpu. Also, taking it one step further and killing the ibus process also doesn't help. Thunderbird keeps using 100% cpu.

I conclude from this that ibus is probably not the root cause of this problem. It's probably a Thunderbird/compiz incompatibility that is somehow causing ibus to refresh itself continuously.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Olaf Dietsche (olaf.dietsche)]

Same here with trusty. ibus-daemon, thunderbird, ibus-ui-gtk3, compiz, ibus-engine-sim are busy and freezing desktop.
Switch to another desktop with Ctrl-Alt-Fxx is possible, but very slow.

top output:

top - 15:50:43 up 16 days, 21:59, 8 users, load average: 8,73, 6,17, 3,25
Tasks: 477 total, 6 running, 471 sleeping, 0 stopped, 0 zombie
%Cpu(s): 19,9 us, 7,2 sy, 0,0 ni, 72,6 id, 0,1 wa, 0,1 hi, 0,0 si, 0,0 st
KiB Mem: 8068688 total, 7866640 used, 202048 free, 880 buffers
KiB Swap: 8278012 total, 1812148 used, 6465864 free. 948104 cached Mem

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
16813 margit 20 0 709396 275956 1648 R 65,2 3,4 11:48.03 ibus-daemon
 7265 margit 20 0 880644 179732 11220 R 34,0 2,2 7:39.09 thunderbird
15897 root 20 0 367452 58056 41540 S 19,8 0,7 41:59.70 Xorg
16954 margit 20 0 5092608 4,366g 4120 S 17,0 56,7 4:08.19 ibus-ui-gtk3
17398 margit 20 0 1825564 97948 6044 R 14,2 1,2 53:39.94 compiz
17284 margit 20 0 511852 316028 1520 S 11,3 3,9 1:48.83 ibus-engine-sim
 9263 olaf 20 0 30772 1552 1052 R 5,7 0,0 0:00.03 top
16873 margit 20 0 637356 5576 2844 S 5,7 0,1 0:58.84 bamfdaemon
    1 root 20 0 33932 1088 680 S 0,0 0,0 0:05.13 init
    2 root 20 0 0 0 0 S 0,0 0,0 0:00.24 kthreadd
    3 root 20 0 0 0 0 S 0,0 0,0 0:03.36 ksoftirqd/0
    5 root 0 -20 0 0 0 S 0,0 0,0 0:00.00 kworker/0:0H
    7 root 20 0 0 0 0 S 0,0 0,0 0:52.43 rcu_sched
    8 root 20 0 0 0 0 S 0,0 0,0 0:25.40 rcuos/0
    9 root 20 0 0 0 0 S 0,0 0,0 0:25.45 rcuos/1