Re: Journaling pointless with today's hard disks?

Pavel Machek (pavel@suse.cz)
Tue, 27 Nov 2001 02:39:24 +0000


Hi!

> > "Power off during write operations may make an incomplete sector which
> > will report hard data error when read. The sector can be recovered by a
> > rewrite operation."
>
> So the proper defect management would be to simply initialize the broken
> sector once a fsck hits it (still, I've never seen disks develop so many
> bad blocks so quickly as those failed DTLA-307045 drives I had).
>
> Note, the specifications say that the write cache setting is ignored
> when the drive runs out of spare blocks for reassignment after defects
> (so that the drive can return the error code right away when it cannot
> guarantee the write actually goes to disk).

They should turn off write-back after number-of-spare-block < cache-size,
otherwise they are not safe.
Pavel

-- 
Philips Velo 1: 1"x4"x8", 300gram, 60, 12MB, 40bogomips, linux, mutt,
details at http://atrey.karlin.mff.cuni.cz/~pavel/velo/index.html.

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