[ale] ff cpu usage jumps to 50% with all tabs minimized

[Alex Carver]

On 3/11/2013 13:26, Ron Frazier (ALE) wrote:
> Hi all,
>
> I've been experiencing a strange problem and I thought I'd mention it
> since others might be seeing it.  I'm using Firefox in Windows 7.  This
> may apply to Linux too, but I don't know for sure.  I have 6 FF windows
> open and maybe 80 tabs total.  When I MINIMIZE all the FF windows, the
> cpu usage on my Pentium dual core system jumps to 55% or so and stays
> there.  As soon as I display one of the FF windows, it goes back down to
> its normal idle of around 10%.  Just a few minutes ago, I restarted FF
> and allowed it to update from version 19.0 to 19.0.2.  This MAY have
> solved the problem.  I haven't seen the CPU staying way up high since
> then.  I'll follow up if I see it again, but I just wanted to see if
> anyone else had noticed this.
>

I believe it's a garbage collection/cache issue.  FF attempts to cache 
anything not visible to reduce its footprint in active memory (a 
frequent complaint that it leaks).  When you minimized everything, you 
probably saw the system dumping to cache and also running the GC 
procedure.  It would have relinquished CPU eventually.

It's had a long history of memory leaks especially in the graphics and 
also in active pages (AJAX) but for some reason no one can or will fix 
it so it continues to leaks.  I've taken to sequestering heavy AJAX 
pages in Chrome instead and leaving FF to handle normal sites.