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From: Graham Cobb <g.btrfs@cobb.uk.net>
To: linux-btrfs@vger.kernel.org
Subject: Extents for a particular subvolume
Date: Wed, 3 Aug 2016 20:56:01 +0100	[thread overview]
Message-ID: <57A24C51.2050302@cobb.uk.net> (raw)

Are there any btrfs commands (or APIs) to allow a script to create a
list of all the extents referred to within a particular (mounted)
subvolume?  And is it a reasonably efficient process (i.e. doesn't
involve backrefs and, preferably, doesn't involve following directory
trees)?

I am not looking to relate the extents to files/inodes/paths.  My
particular need, at the moment, is to work out how much of two snapshots
is shared data, but I can think of other uses for the information.

Graham

             reply	other threads:[~2016-08-03 20:20 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-08-03 19:56 Graham Cobb [this message]
2016-08-03 20:37 ` Extents for a particular subvolume Adam Borowski
2016-08-03 21:55   ` Graham Cobb
2016-08-04 11:34     ` Austin S. Hemmelgarn
2016-08-15 19:18     ` Graham Cobb

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