Re: Ridiculous load

On Sat, 11 Dec 2004 10:44:59 -0600, Wes wrote:
> On 12/9/04 9:23 AM, "Peter Haworth" <pmh@edison.ioppublishing.com> wrote:
>
> > It runs RHEL ES v3, kernel 2.4.21-20.ELsmp
> > It's generally a very stable box which runs a number of postgresql
> > instances.  But last night we hit very high low averages - 10+, vs the
> > normal 0-2.
> > The culprit appeared to be kswapd, which was using huge amounts of cpu.
> > I'd like to know why!
>
> There were some major changes in swap management somewhere in the linux 2.4
> kernel (also RH 3.0 ES).  I don't off hand remember exactly which level.
> Under a heavy I/O load, we also saw kswapd going nuts with the 2.4.21
> kernel, destroying system performance.  The only solution we found was to
> upgrade to a 2.6 kernel.

We've now upgraded to RedHat's 2.4.21-25.ELsmp, which seems to have fixed
things.

--
    Peter Haworth    pmh@edison.ioppublishing.com
"Back then, I remember wondering how come he accepted my offer instead
 of doing something sensible like, say, running away screaming."
        -- Yanick Champoux, on being a Perl Golf referee