Re: [PATCH] kswapd fix & logic improvement

Michael L. Galbraith (mikeg@weiden.de)
Tue, 3 Mar 1998 17:10:28 +0100 (MET)


On Tue, 3 Mar 1998, Rik van Riel wrote:

> On Tue, 3 Mar 1998, Michael L. Galbraith wrote:
>
> > I was able to stimulate a 'swap-attack' which took almost a hour to
> > recover control from.
> >
> > 2.1.89pre5 + swap patch
>
> To 'recover from' or 'handle' your attack (180+ mb working
> set on an 80 mb machine) is going to need 'real' swapping,
> ie. the temporary suspension of processes to reduce VM load.
>
> I'd like you to try to even start your stress test under a
> normal kernel (it'll probably work, but not without the
> neccesary oom()s and signal 7s).
>

I've run much larger working sets on this machine without either
losing control or having the tasks killed. I've run simulations
which ate 400+ Mb. The realtime aspect was a joke, but it worked.

> This patch is only an improvement for normal use. Anyways,
> thrashing can't be combatted by paging algorithms, no matter
> how good.
>

OK.. thought you wanted it pounded upon.

It was running fine with all tasks being scheduled smoothly until
something triggered a mega-thrash.

> I'll be working on the swapping daemon as soon as I've got
> the current patch sorted out...
>

Turned out the kswapd messages weren't related to the thrashing.
I would have seen it if I hadn't jumped straight into X.

-Mike

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu