Why use swap when there is RAM free?

[Rashkae]

Smoot Carl-Mitchell wrote:

> 
> Are you sure your not talking about the disk cache which will write
> through memory pages to disk files periodically to prevent file
> corruption?  This is cached memory in "top" and some of the other tools
> to display memory statistics.  These pages are never written to swap.
> Also read only executable code pages are not written to swap, since the
> backing store is the file where the executable resides.
>


http://en.wikipedia.org/wiki/Paging