From: David MacKinnon <blaedd@gmail.com>
To: linux-btrfs@vger.kernel.org
Subject: Re: Recovering from csum errors
Date: Tue, 3 Sep 2013 19:26:10 +1000 [thread overview]
Message-ID: <CAA1QwTbiYGWpxctxOrF67wOzdAr6U6TKR__HZW44c2q9XeVM2w@mail.gmail.com> (raw)
In-Reply-To: <pan$97a5$71cfb7f0$286a61f9$62ed2e15@cox.net>
On 3 September 2013 18:54, Duncan <1i5t5.duncan@cox.net> wrote:
>
> > In case the data is wrong, there may be a reverse CRC32 algorithm
> > implemented. Most likely it's only several bytes which got "flipped".
>
...
>
> But... that flips the entire reason for choosing direct-IO in the first
> place -- performance -- on its head, incurring a **HUGE** slowdown just
Not wanting to put words in the original posters mouth, but I read
that as an offline recovery method (scrub?), rather than real time
recovery attempts. If the frequency of errors is low, then for certain
purposes accepting, a few errors if you had a recovery option might be
acceptable.
As mentioned, nocow is probably best for VM images anyhow, but still :)
-David
next prev parent reply other threads:[~2013-09-03 9:26 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-02 21:41 Recovering from csum errors Rain Maker
2013-09-02 22:00 ` Hugo Mills
2013-09-02 22:28 ` Rain Maker
[not found] ` < CAD+_0YqsQRO90Lx1R64h8EE-L=4zrE6CEQGDKy-h=92hLLptWw@mail.gmail.com>
2013-09-03 8:54 ` Duncan
2013-09-03 9:26 ` David MacKinnon [this message]
[not found] ` < pan$97a5$71cfb7f0$286a61f9$62ed2e15@cox.net>
[not found] ` < CAA1QwTbiYGWpxctxOrF67wOzdAr6U6TKR__HZW44c2q9XeVM2w@mail.gmail.com>
2013-09-03 16:08 ` Duncan
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