Re: Time for a pre-patch-2.0.31-3?

Richard Waltham (dormouse@farsrobt.demon.co.uk)
Thu, 3 Jul 1997 12:21:10 +0100 (BST)


Andi Kleen wrote:
>
> Richard Waltham <dormouse@farsrobt.demon.co.uk> writes:
>
> > Hi,
> >
> > Have you checked what happens to disk read performance?
> >
> > With 2.0.29, and 2.0.30 with Pavel Krauz patch, Bonnie gives something like
> >
> > -------Sequential Output-------- ---Sequential Input-- --Random--
> > -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks---
> > Machine MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU /sec %CPU
> > 100 2259 77.0 4873 28.5 1768 20.5 2119 76.9 4114 20.4 118.8 5.3
> >
> >
> > And with your latest patch with pre-patch 2.0.31-2
> >
> > -------Sequential Output-------- ---Sequential Input-- --Random--
> > -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks---
> > Machine MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU /sec %CPU
> > 100 2262 76.8 4841 30.6 1362 15.5 1445 52.7 1568 7.6 120.1 5.3
> >
> > Note the drastic fall in read performance. :( These results are consistent.
>
> I rememember the original port of the 2.1 buffer.c into 2.0.30 was inspired
> by this read performance problem. Leonard Zubkoff presented a patch for it
> at this time. Maybe he knows how to fix it. It *should* be fixed for 2.0.31.
>
> -Andi
>

The drop in read performance occurs only when Werner's patch is included on
top of pre-patch-2.0.31-2. Without Werner's patch pre-patch-2.0.31-2
performance is similar to 2.0.29, 2.0.30.

And as you've CC'd this to Leonard this is including a scsi patch supplied recently
by Leonard.

Richard

>
> >
> >
> > Richard
> >
> >
> >
> > Dr. Werner Fink wrote:
> > >
> > >
> > > Hi,
> > >
> > > here is the collected patch against pre-patch-2.0.31-2. The buffer code
> > > is based on the NEW buffer-code of 2.0.30. I've added some old own and old
> > > foreign changes (let's look into http://www.linuxhq.com/patch/20-p0595.html):
> > >
> >
> >
> > --
> > Richard Waltham | Work: richard@digtalinterface.demon.co.uk
> > At home in | Home: dormouse@farsrobt.demon.co.uk
> > Southampton UK | Compuserve 100421.1276
>

-- 
 Richard Waltham   |               Work: richard@digtalinterface.demon.co.uk
   At home in      |               Home:       dormouse@farsrobt.demon.co.uk
 Southampton UK    |                                  Compuserve 100421.1276