Re: poor SATA performance under 2.6.11 (with < 2.6.11 is OK)?

From: Tomasz Torcz
Date: Thu Apr 14 2005 - 18:07:40 EST


On Fri, Apr 15, 2005 at 12:08:15AM +0200, Tomasz Chmielewski wrote:
> >>The performance under 2.6 kernels is *very* poor (Timing buffered disk
> >>reads never more than 20 MB/sec); under 2.4 it runs quite fine (Timing
> >>buffered disk reads around 60 MB/sec).
> >
> >
> > 2.4 risk data corruption. 2.6 sata_sil.c contains blacklist for some
> >driver-controller combination.
> >
> > See: http://home-tj.org/m15w/
>
> ...but this link just doesn't explain why performance is sooo bad with
> 2.6.11.x kernels (Timing buffered disk reads at 10-20 MB/sec), and is
> just OK with older 2.6 kernels (Timing buffered disk reads even at about
> 100 MB/sec with 2.6.8.1).
>
> any clue?

The sata_sil blacklist grown over time. Older version didn't mark your
drive as bad. Check sata_sil history at
http://www.linuxhq.com/kernel/file/drivers/scsi/sata_sil.c ,
you may find exact time when your drive got blacklisted.

--
Tomasz Torcz To co nierealne - tutaj jest normalne.
zdzichu@xxxxxxxxxxxxxxxxx Ziomale na życie mają tu patenty specjalne.

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