Runaway threads get 100% of the CPU



14 years ago
13 years ago


(Reporter: dejan, Unassigned)


Firefox Tracking Flags

(Not tracked)




14 years ago
User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8b) Gecko/20050217 MultiZilla/
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8b) Gecko/20050217 MultiZilla/

After running for a while usually one, sometimes more threads get 100% of the
CPU usage although the browser might be in the background, not doing anythig.

I'm running on a dual Xeon with hyperthreading enabled (4 logical CPUs) so
sometimes Mozilla gets 25% (90% of the cases) and sometimes 50% of the total CPU

Even when this happens I can work and the application is stable, but in order to
free the CPU I need to restart it.

Reproducible: Sometimes

Steps to Reproduce:

Expected Results:  
Normal CPU usage.

Comment 1

14 years ago
please try without multizilla

Comment 2

14 years ago
I uninstalled MultiZilla yesterday and this morning the mozilla process was
getting 25% of the CPU again so Multizilla is not to blame.

Comment 3

14 years ago
Is there a way on Windows to get a thread dump of the Mozilla process so that
one can see which thread is getting all of that CPU time?

Comment 4

14 years ago
does the CPU usage continue if you close everything except 1 window, open a new
window and then close the 1 window that you left open?

Also please try a clean profile (mozilla -profilemanager)

Comment 5

14 years ago
I had already tried that (closing all windows, then opening a new window and
then closing the previously opened window) and the CPU usage stays high.

I'll try with a new profile later today and see if it helps.
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Last Resolved: 13 years ago
Resolution: --- → EXPIRED
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