On Wednesday 21 April 2004 11:27, Martin Svensson wrote:
> > It is perfectly sane to swap out something unused
> > (think about getties which are unused for weeks)
> > in order to free some RAM for file cache.
> >
> > The question is, how aggressive to be with it.
> >
> > You can:
> > * play with /proc/sys/vm/swappiness
> > * run without swap at all, you seem to have enough
> > memory for that
> >
> > I run some of my boxes swapless, it works

>
> If it swapped out 20-100MB I wouldn't care, but now
> it's constantly rising up to 600MB swap.. all the
> getties in the world don't use up 600MB :-)


Yeah, kernel swapped out pages of other, larger processes
as well, including squid. This sounds bad, squid's pages
are unlikely to be 'unused for weeks'.

2.4 won't be tweaked in this regard, it entered 'stable'
state. If you want to get it fixed by kernel folks,
you have to move to 2.6.

> /proc/sys/vm/swappiness is a new feature in 2.6 right?
> I don't see it on this box running
> "2.4.21-9.0.1.ELsmp".


Run without swap then. If the problem was 'bad'
swapping decisions made by kernel, it will stop happening
since there won't be any swap to misuse

OTOH, if you will start running into OOM,
*then* there is definitely a problem
with some process growing too big.
--
vda