Berkeley paging

[Dave Cohrs]

Even if you were to put a real working set scheme (or even WS-clock,
which might satisfy the spirit-of-UNIX argument you guys brought up)
into UNIX, you'd still need some kind of global policy.  You don't want
one process to take over all of memory; remember, working set isn't
fixed sized (which is why the VMS policy isn't really working set, or
wasn't last time I checked), it's defined over a time interval.  A
memory load balance policy is necessary, and you still need to swap
processes when memory gets over-committed.

If you have the hardware support, working set, or WS-clock would
probably be a win, even in UNIX.  Of course, if your machine doesn't
have enough memory in the first place, no memory management policy is
going to help; you'll need to spend some $$.

Rule #1 in paging:  It's great until you have to use it.

--
Dave Cohrs
+1 608 262-6617                        UW-Madison Computer Sciences Department
dave at cs.wisc.edu                 ...!{harvard,ihnp4,rutgers,ucbvax}!uwvax!dave