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From: Zoiled <zoiled@online.no>
To: cwillu <cwillu@cwillu.com>
Cc: Stefan Behrens <sbehrens@giantdisaster.de>,
	Hugo Mills <hugo@carfax.org.uk>, Waxhead <waxhead@online.no>,
	linux-btrfs@vger.kernel.org
Subject: Re: Will BTRFS repair or restore data if corrupted?
Date: Thu, 26 Jan 2012 21:27:22 +0100	[thread overview]
Message-ID: <4F21B72A.4050805@online.no> (raw)
In-Reply-To: <CAE5mzvhMxQ-Xs2MSrTs4jcJjcL_L34AQ+rX7-j9ept9keGCU+Q@mail.gmail.com>

cwillu wrote:
>> So if I for example edit a text file three times and store it I can get the
>> following.
>> Version1: I currently like cheese
>> Version2: I currently like onions
>> Version3: I currently like apples
>> As far as I understand a disk corruption might result in me suddenly liking
>> onions (or even cheese) instead of apples without any warning except in
>> syslog.?! I really hope I have misunderstood the concept and that there is
>> some error correction codes somewhere.
> Yes, you've completely misunderstood the concept :p
>
> There are crc's on each 4k block of data; if one copy fails the
> checksum, and a second copy is available, and that copy does match,
> then the good data will be returned and btrfs will overwrite the
> corrupted copy with the good copy.  If there isn't another copy, then
> an io error will be returned instead.
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
>
>
Phew... that sounds better :)

      reply	other threads:[~2012-01-26 20:27 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-25 23:27 Will BTRFS repair or restore data if corrupted? Waxhead
2012-01-26  7:19 ` Chester
2012-01-26  8:59 ` Hugo Mills
2012-01-26  9:33   ` Stefan Behrens
2012-01-26 19:16     ` Zoiled
2012-01-26 20:22       ` cwillu
2012-01-26 20:27         ` Zoiled [this message]

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