what means it that firefox keeps greying out?

[J]

On Wed, May 12, 2010 at 08:43, Pat Brown <pat.mysterywriter at gmail.com> wrote:
> On Wed, May 12, 2010 at 6:30 AM, Robert P. J. Day <rpjday at crashcourse.ca>
> wrote:
>>  i'm not sure if this is related to my running a 2.6.34-rc7 kernel
>> but, recently (within the last day or so), i've had my firefox session
>> suddenly go dim/grey, and become totally unresponsive.  it *appears*
>> to be related to when it's trying to load a page, but i've never seen
>> this behaviour before on any distro.
>>
>>  in some cases, if i just wait, it will come back; in other cases,
>> it's a lost cause and i have to kill firefox.  in an extreme case, i
>> had to power down the entire machine and reboot.
>>
>>  anyone else seeing this?  thoughts?
> Mine does that all the time. I run System Monitor all the time and when that
> happens I go to the monitor and Firefox is always hogging around 300 MB of
> Memory and is Uninterruptable. I notice it happens more when I have Facebook
> open. Since Facebook is a live feed, it updates constantly and I think
> that's what hogs the memory.
>
> I figured it was the low memory I have on my laptop. I have less than 500 MB
> of Memory

See my post... the key is uninterruptable...

As memory usage grows across your open apps, as well as CPU usage,
this will happen.  I can usually get it to happen across many apps,
especially when I have FF open with several tabs as well as other apps
based on Java or other such environments.

It used to be the application in question (whatever it is that's in an
uninterruptable state) would do nothing, and appear hung when it was
just waiting on IO or queued, or who knows what.  Somewhere in the
recent past, the window darkening feature was added so you'd at least
have some indication that the app is "on hold".

I have no idea exactly when that was added in, other than within the
last few years though :(

Jeff