Weird Firefox performance issue

Adam Pribyl pribyl at
Tue May 1 17:53:15 UTC 2012

On Tue, 1 May 2012, Pedro Francisco wrote:

> On Tue, May 1, 2012 at 2:50 PM, Jonathan Kamens <jik at> wrote:
>> I thought I would try moving my profile out of the way to see if performance
>> would improve, so I shut down Firefox and moved ~/.mozilla/firefox/*.default
>> somewhere else. But then when I tried to restart Firefox, it said that it
>> was already running but not responding. Clearly moving the *.default
>> directory isn't the way to go.
> You have to have the profile directory there otherwise Firefox can't
> check if it is open already.
> Try something like
> ~.mozilla/firefox $ for i in *.default ; do mv $i OLD.$i; mkdir $i; done
> And you can open Firefox with a clean profile.
> Alternatively,
> ~.mozilla/firefox $ mv profiles.ini OLD.profiles.ini
> And then Firefox will think it is being opened for the first time.
> Concerning the slowness being gone, maybe it was just luck?

IMHO it was the restart that "fixed" it. I experience this "getting slow" 
think to happen for a long time. After several days of run, firefox needs 
to be restarted. 1. it's taking too much RAM, 2. usually causing higher 
CPU load than after restart with same tabs and history open. BTW: same I 
have to do with gnome-shell, so maybe some graphics card driver is 

> -- 
> Pedro

Adam Pribyl

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