From: Roman Mamedov <rm@romanrm.net>
To: Alexander Tomokhov <alexoundos@ya.ru>
Cc: "linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>
Subject: Re: Does data checksumming remain for files with No_COW file attribute?
Date: Sat, 24 Sep 2016 17:40:12 +0500 [thread overview]
Message-ID: <20160924174012.51d44caa@natsu> (raw)
In-Reply-To: <767591474719974@web21o.yandex.ru>
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On Sat, 24 Sep 2016 15:26:14 +0300
Alexander Tomokhov <alexoundos@ya.ru> wrote:
> does setting No_COW on a file (chattr +C) imply disabling data checksumming on it?
Yes. IIRC the reasoning was that it's more difficult to track checksums of
data which is being overwritten in-place (as opposed to CoW).
> may it disable checksumming only for newly written extents and keep for reading existing ones?
You can't apply chattr +C to any files of non-zero length, so by definition
there won't be any pre-existing checksummed extents in that file.
--
With respect,
Roman
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next prev parent reply other threads:[~2016-09-24 12:40 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-24 12:26 Does data checksumming remain for files with No_COW file attribute? Alexander Tomokhov
2016-09-24 12:37 ` Hugo Mills
2016-09-24 23:25 ` Alexander Tomokhov
2016-09-24 23:50 ` Adam Borowski
2016-09-25 5:44 ` Duncan
2016-09-26 20:41 ` Adam Borowski
2016-09-24 12:40 ` Roman Mamedov [this message]
2016-09-24 12:43 ` Hugo Mills
2016-09-24 18:11 ` Christoph Anton Mitterer
2016-09-25 13:49 ` Goffredo Baroncelli
2016-09-25 19:53 ` Christoph Anton Mitterer
2016-09-26 11:11 ` Austin S. Hemmelgarn
2016-09-24 18:09 ` Christoph Anton Mitterer
2016-09-24 21:44 ` Adam Borowski
2016-09-24 22:52 ` Christoph Anton Mitterer
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