Kernel swapping parameters

[jmc at root44.UUCP]

Has anyone ever looked particularly at 'inage' and 'outage' in sched() in
slp.c in the kernel, which are used to decide which processes should be
swapped out/in?

These are compared with the 'magic' amount of 2 seconds, without any indication
of where '2' came from.  This seems to be in all USG-derived systems.

Recently we had a customer (with a very slow disk) complaining about the amount
of time his system took, and I put in (just out of curiousity) a hack to vary
these parameters on the fly and I was STAGGERED by the difference.  I got over
a TENFOLD improvement in response time by upping both to 8.

Any comments would be welcome.

Thanks		John Collins
		Root Computers Ltd
			...!vax135!ukc!root44!jmc