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Date: Mon, 2 Dec 2002 16:14:16 -0700
From: Andreas Dilger <adilger@clusterfs.com>
To: John Bradford <john@grabjohn.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: More intellegent bad block reallocation in software?
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On Dec 02, 2002  23:20 +0000, John Bradford wrote:
> My idea is that we could allocate one block out of every ten to be a
> spare block, (which would reduce disk capacity by 10%), and then if a
> block needed to be re-allocated, we could allocate one from the same
> cylinder, therefore removing the need for the heads to seek across the
> disk.
> 
> How easily could this be added to existing filesystems?  Presumably
> we'd need extra functionality in both filesystem code and the IDE and
> SCSI code, and I realise that it might be completely impossible,
> without custom firmware on the disk.  It's an interesting idea
> though.

Even better - just ignore bad blocks and don't relocate them at all.
That's what ext2/3 do - just skip those blocks and avoid the seek
entirely.

Cheers, Andreas
--
Andreas Dilger
http://sourceforge.net/projects/ext2resize/
http://www-mddsp.enel.ucalgary.ca/People/adilger/

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