On Wed, Dec 17, 2003 at 09:20:12PM +0000, Matthias Scheler wrote:
> In article <20031216195451.GB1257@antioche.eu.org>,
> 	Manuel Bouyer <bouyer@antioche.eu.org> writes:
> > If I remember well, the real limit is 128k, by setting the sector count to 0.
> > I guess we'll find broken drives that won't handle this properly :(
> 
> When Commodore tried to use multi sector read upto 128KByte in the
> IDE driver of the A600, A1200 and A4000 it turned out that there
> are three classes of drives:
> 
> 1.) Drives which can handle 128KByte.
> 2.) Drives which can handle 128KByte - 1 block.
> 3.) Drives which can handle 64KByte.
> 
> Drives in class 2. or 3. caused data corruption when used with too high
> sector counts. The usual work arround was to limit the I/O size using
> a certain filesystem parameter.

Thanks for the info. I'll have that in mind when we'll go to 128k I/O for
IDE. As FreeBSD is using 128k I/O for IDE I guess they have started a list
of bad drives.

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
     NetBSD: 23 ans d'experience feront toujours la difference
--