On Mon, Oct 02, 2000 at 02:35:57PM -0700, Jeremy C. Reed wrote:

 > I read (exim mailing list) that "... Linux tries to avoid using swap at
 > all costs, *BSD will swap out processes that have been idle for "X" amount
 > of time ...".

That is flatly incorrect.  NetBSD won't swap out a process that has been
idle for "X" amount of time.  It only selects processes for swapping when
absolutely necessary.

It will clean pages to swap space (not the same as swapping pages) if we
are below the target free page count and the pages are "idle" (have not
been referenced) for some period of time.

 > Can someone explain how and when BSD swaps?

Not in a few short senteces.  There are entire dissertations written
on the subject.

-- 
        -- Jason R. Thorpe <thorpej@zembu.com>