Why am I using swap?

[Dan Track]

On 8/8/05, Jeff Vian <jvian10 at charter.net> wrote:
> On Mon, 2005-08-08 at 16:40 +0100, Dan Track wrote:
> > HI
> >
> > I just rebooted my workstation, and I ran a "free -m". I realised that
> > I'm already using swap even though I've got so much free ram. Anyone
> > know why this is?
> >
> > free -m
> >              total       used       free     shared    buffers     cached
> > Mem:          1244       1227         17          0         37        636
>                                     ^^^^^^^^
> What do you mean "so much free ram".  Whatever you have running is using
> almost 99% of your memory and only 17 mb free. While that small amount
> free is normal on my systems, the amount used is much higher than I
> routinely run.  The tiny amount of swap used (13 mb) is insignificant.
> 
> > -/+ buffers/cache:        553        691
> > Swap:         1993         13       1979
> >
> 
> This is mine after running for more than 5 days.
>  $ free -m
>          total      used     free   shared  buffers   cached
>  Mem:     1011       991       19        0       13      703
>  -/+ buffers/cache:  274      736
>  Swap:    1023         0     1023
> 
> >

Hi

Thanks for the reply. The problem is that the system has only been up
for 2 minutes. With no additional services started apart from the
basic set of strtup services found in a default install. I understand
the linux kernel caches all the freely available memory in order to
make use of it, but why is is swapping within two minutes of bootup
when the line:

-/+ buffers/cache:        553        691

shows there is still 691 MB free?

Additionally is it true that the linux kernel can only take up to a
maximum of 800Mb for kernel usage while the rest is left for user
space?

Thanks
Dan