From: Greg Freemyer <greg.freemyer@gmail.com>
To: Dawning Sky <the.dawning.sky@gmail.com>
Cc: linux-raid@vger.kernel.org
Subject: Re: Disk I/O error while rebuilding an md raid-5 array
Date: Mon, 8 Feb 2010 19:04:14 -0500 [thread overview]
Message-ID: <87f94c371002081604g37984161h2ba65bd193714780@mail.gmail.com> (raw)
In-Reply-To: <adf93d751002081523y1b9de656kdbba276b3dbc6af4@mail.gmail.com>
>
> PS, if in the end I have to build a new array, I'll probably go with a
> raid 6 instead.
Agreed, someone recently posted that for a raid-5 composed of 1TB
drives the odds of a rebuild failure are 1 in 67 even if the remaining
drives are within spec. (ie. the unrecoverable bit error rate is
slowing succumbing to the ever increasing size of drives.)
You have 500GB drives, but you have 3 left to rebuild from, so that's
1.5 TB your trying to read. I'm not sure how the original calculation
was done, so your odds of failed rebuild were either 1 in 134 or about
1 in 42. Either not very good for something that is supposed to
protect your data.
Greg
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next prev parent reply other threads:[~2010-02-09 0:04 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-02-08 23:23 Disk I/O error while rebuilding an md raid-5 array Dawning Sky
2010-02-09 0:04 ` Greg Freemyer [this message]
2010-02-09 0:45 ` Dawning Sky
2010-02-09 10:22 ` Jon Hardcastle
2010-02-09 11:57 ` John Robinson
2010-02-09 17:43 ` Dawning Sky
2010-02-09 19:28 ` Mikael Abrahamsson
2010-02-09 1:23 ` Dawning Sky
2010-02-09 4:24 ` Wil Reichert
2010-02-09 4:26 ` Steven Haigh
2010-02-09 4:37 ` Wil Reichert
2010-02-09 4:20 ` Dawning Sky
2010-02-09 6:57 ` Stefan Hübner
2010-02-09 7:39 ` Dawning Sky
2010-02-09 8:05 ` Mikael Abrahamsson
-- strict thread matches above, loose matches on Subject: below --
2010-02-09 0:25 russ
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