Re: Adaptive Readahead V14 - statistics question...

Voluspa
2006-06-01T06:36:52Z

On Thu, 1 Jun 2006 13:51:43 +0800 Fengguang Wu wrote:
> On Wed, May 31, 2006 at 11:50:21PM +0200, Voluspa wrote:
> > _Massive READ_
> >
> > [/usr had some 490000 files]
> >
> > "cd /usr ; time find . -type f -exec md5sum {} \;"
> >
> > 2.6.17-rc5 ------- 2.6.17-rc5-ar
> >
> > real 21m21.009s -- 21m37.663s
> > user 3m20.784s -- 3m20.701s
> > sys 6m34.261s -- 6m41.735s
> >
> > I had planned to run this at least three times, but didn't realize I had
> > 12 compiled kernel trees and 3 uncompiled there... So, a one-shot had to
> > do. But it's still significant.
>
> Sorry, it is a known regression. I'd like to fix it in the next
> release.

That's cool. I had fun testing (I'm weird) and now have a fixed procedure
to monitor your future work. When/if it hits mainline I'll both back it out
and switch it on/off. Then shout WOLF if I see a regression anywhere ;)

There's still the readahead size to adjust. I'll return with my findings.

Mvh
Mats Johannesson
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