From: Duncan <1i5t5.duncan@cox.net>
To: linux-btrfs@vger.kernel.org
Subject: Re: Meaning of \"no_csum\" field when scrubbing with -R option
Date: Fri, 21 Feb 2014 08:00:55 +0000 (UTC) [thread overview]
Message-ID: <pan$a9781$e2170d79$56defdc9$40402ab8@cox.net> (raw)
In-Reply-To: 5306BA41.1060700@cn.fujitsu.com
Wang Shilong posted on Fri, 21 Feb 2014 10:30:25 +0800 as excerpted:
>>>> So my question is, why does scrub show a high (i.e. non-zero) value
>>>> for no_csum? I never enabled nodatasum or a similar option.
> This should be related to btrfs free space cache, it is designed as
> nocow without checksums.
That's a reasonable explanation. Thanks. =:^)
(And anyway, if the space-cache gets corrupted, there are mount options
to clear it, etc, and it's easily rebuilt even if it takes long enough
keeping the cache is useful in general, so it's not a huge deal needing
checksummed.)
--
Duncan - List replies preferred. No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master." Richard Stallman
prev parent reply other threads:[~2014-02-21 8:01 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-02-19 12:58 Meaning of "no_csum" field when scrubbing with -R option Sebastian Ochmann
2014-02-20 10:31 ` Duncan
2014-02-20 10:51 ` Wang Shilong
2014-02-20 11:16 ` Duncan
2014-02-20 11:25 ` Meaning of \"no_csum\" " Sebastian Ochmann
2014-02-20 12:38 ` Wang Shilong
2014-02-21 2:30 ` Wang Shilong
2014-02-21 8:00 ` Duncan [this message]
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