Re: Linux 2.4.5-ac2

Marcelo Tosatti
2001-05-28T22:52:18Z

On Tue, 29 May 2001, André Dahlqvist wrote:

> André Dahlqvist <anedah-9@sm.luth.se> wrote:
>
> > I agree. Kernels after 2.4.4 uses a *lot* more swap for me, which I guess
> > might be part of the reason for the slowdown.
>
> Following up on myself, here are some numbers:
>
> Freshly booted 2.4.4 with X and Mozilla running, 'free' outputs this:
>
> total used free shared buffers cached
> Mem: 62716 61280 1436 0 1820 28704
> -/+ buffers/cache: 30756 31960
> Swap: 160608 0 160608
>
> Freshly booted 2.4.5-ac2 with X and Mozilla running, 'free' outputs this:
>
> total used free shared buffers cached
> Mem: 62784 61784 1000 380 1824 35748
> -/+ buffers/cache: 24212 38572
> Swap: 160608 7128 153480
>
> After running 2.4.5-ac2 (and other kernels after vanilla 2.4.4) for a while
> the swap usage grows a lot, to around 60 MB. Older kernels didn't swap out
> this aggressively in my experience.

Well, they probably did. Its just that the kernel released unused swap
cache pages (thus releasing swap space) "more often".

Just to confirm this is what happening in your case: Can you please try
2.4.4-ac5 and see if the _swap usage_ is still as badly?

This kernel contains a workaround to make the VM release unused swap cache
pages more often. (note: newer 2.4.4-ac do not contain the patch because
it could cause locks under some cases. Specially swap to files)

Back to the interactivity issue, I suppose you've "felt" bad interactivity
with 2.4.* kernels, right ?

I am asking that because I do not believe this swap usage issue is the
main reason for the problem.