Re: kswapd etc hogging machine

[Andrew Morton <akpm@zip.com.au>]

Alan Cox wrote:
> 
> > But Art's kernel (what kernel is in RH7.2 anyway?  2.4.9 with vendor
> > hacks^Wfixes, I think) is nowhere near that stage.
> 
> 7.2 is 2.4.7-ac ish, 7.2 + errata is 2.4.9-ac ish

OK, thanks.

> > The good news is that 2.4.17 has pretty much slain this dragon.  The
> > -aa patches are better still, and 2.4.18 will be even better than
> > that.
> 
> Bollocks. I get regular mails from large numbers of people who are stuck
> at 2.4.12/13-ac and are hoping I'll do an update because their machines
> die in hours or run 25-50% slower with 2.4.1x.

I was referring to the swap and evict in the presence of heavy write
traffic.

> 2.4.1x VM code is performing better under light loads but its absolutely
> and completely hopeless under a real paging load. 2.4.17-aa is somewhat
> better interestingly.
> 

s/interestingly/frustratingly/.  -aa has some interesting changes to
the write scheduling as well.  I just wish I knew what problem they're
solving.

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