From: CSights <csights@fastmail.fm>
To: linux-btrfs@vger.kernel.org
Subject: metadata copied/data not copied?
Date: Mon, 16 Mar 2009 10:35:19 -0400 [thread overview]
Message-ID: <200903161035.19446.csights@fastmail.fm> (raw)
Hi everyone,
I'm curious what would happen in btrfs if the following commands were issued:
# cp file1 file2
# chown newuser:newgroup file2
Where file1 was owned by olduser:oldgroup.
If I understand copy-on-write correctly the "cp" would merely create a new
pointer (or whatever it is called :( ) containing the files' metadata but the
file contents would not actually be duplicated.
Then the "chown" would change the metadata so that file2's metadata indicates
newuser:newgroup owned the file contents. At the same time the metadata of
file1 would say that olduser:oldgroup owned the file contents.
(If a user modified the file contents, the contents would be copied at that
time.)
Thanks, curious newbie,
C.
next reply other threads:[~2009-03-16 14:35 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-03-16 14:35 CSights [this message]
2009-03-16 15:28 ` metadata copied/data not copied? jim owens
2009-03-17 0:25 ` Chris Mason
2009-03-17 15:34 ` CSights
2009-03-17 15:56 ` Chris Mason
2009-03-17 17:08 ` CSights
2009-03-17 17:24 ` Chris Mason
2009-03-16 21:14 ` Dmitri Nikulin
2009-03-16 21:18 ` Dmitri Nikulin
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