From: Sebastian Ochmann <ochmann@informatik.uni-bonn.de>
To: linux-btrfs@vger.kernel.org
Subject: Meaning of "no_csum" field when scrubbing with -R option
Date: Wed, 19 Feb 2014 13:58:17 +0100 [thread overview]
Message-ID: <5304AA69.5020800@informatik.uni-bonn.de> (raw)
Hello everyone,
I have a question: What exactly does the value for "no_csum" mean when
doing a scrub with the -R option? Example output:
> sudo btrfs scrub start -BR /
scrub done for ...
...
csum_errors: 0
verify_errors: 0
no_csum: 70517
csum_discards: 87381
super_errors: 0
...
In the btrfs header, I found the following comment for the "no_csum"
field of the btrfs_scrub_progress struct:
"# of 4k data block for which no csum is present, probably the result of
data written with nodatasum"
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.
Best regards
Sebastian
next reply other threads:[~2014-02-19 13:08 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-02-19 12:58 Sebastian Ochmann [this message]
2014-02-20 10:31 ` Meaning of "no_csum" field when scrubbing with -R option 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
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