Re: disk speed regression kernel 2.6.29 and after

[Arjan van de Ven <arjan@infradead.org>]

On Wed, 23 Sep 2009 22:06:54 -0500
Will <whansard@sbcglobal.net> wrote:

> 
> > On Wed, Sep 23, 2009 at 8:08 AM, will <whansard@sbcglobal.net>
> > wrote:
> > > I had been using an old 2.6.22 kernel on my machine, and I often
> > > backup one partition of my main hard drive to a partition on a
> > > second hard drive. The main hard drive is sata 640 gigs, and the
> > > second is a pata 320 gig. copying this partition from one drive
> > > to the other with dd takes about 3 minutes and 30 seconds. When I
> > > installed kernel 2.6.30, and 2.6.31, the time took 9 minutes and
> > > 20 seconds. I decided to go to the trouble of compiling all the
> > > kernels between, and kernels 2.6.22-2.6.28 all do the operation
> > > in about 3
> > 
> 
> > > the drives
> > > with the kernels 2.6.29 and after.
> > > Please cc me with any followups or anything. thanks
> 
> 295f00042aaf6b553b5f37348f89bab463d4a469 is first bad commit
> commit 295f00042aaf6b553b5f37348f89bab463d4a469
> Author: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> Date:   Fri Jan 2 16:12:48 2009 +0100
> 
>     ide: don't execute the next queued command from the hard-IRQ
> context (v2) 


if you're using CONFIG_IDE.... might be worth switching to the LIBATA
subsystem instead...


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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