Further memory question [was: Clear the computer's memory?]

[Kent Borg]

On Thu, Mar 30, 2006 at 02:29:42PM +0100, R Kimber wrote:
> It's not linux's behaviour that bothers me.  What I'm puzzled about is
> that when I boot up, linux will allocate memory as you describe, and
> Gkrellm will report an amount free. I'm not clear why this free amount
> should change so drastically after some hours of use, when caches etc
> have already been allocated and I'm not starting new apps.  At the
> moment, I still have about 1714MB free, but by tomorrow I'll bet it
> will be down to 700MB.  I don't usually use Firefox, BTW.

Things happen overnight.  The disk is scanned to make an index of
files, the system checks for updates, etc., and you might have set up
cron tasks of your own.  Some of this will land in memory--and it much
will get booted out if memory is really needed to, say, launch
Firefox.  

A really short version of all this might be: "Free" means unused, it
does not mean "unavailable".

-kb