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From: Chris Mason <chris.mason@oracle.com>
To: Thomas Glanzmann <thomas@glanzmann.de>
Cc: Heinz-Josef Claes <hjclaes@web.de>,
	Edward Shishkin <edward.shishkin@gmail.com>,
	Tomasz Chmielewski <mangoo@wpkg.org>,
	linux-btrfs@vger.kernel.org
Subject: Re: Data Deduplication with the help of an online filesystem check
Date: Thu, 4 Jun 2009 08:43:28 -0400	[thread overview]
Message-ID: <20090604124328.GL13945@think> (raw)
In-Reply-To: <20090604120350.GB18999@cip.informatik.uni-erlangen.de>

On Thu, Jun 04, 2009 at 02:03:50PM +0200, Thomas Glanzmann wrote:
> Chris,
> 
> > It is a counter and a back reference.  With Yan Zheng's new format
> > work, the limit is not 2^64.
> 
> That means that there is one back reference for every use of the block?
> Where is this back reference stored? (I'm asking because if one back
> reference for every copy is stored, it can obviously not be allocated
> statically).

These are all stored in the extent allocation tree.  There isn't exactly
a 1:1 mapping but it is effectively that.

-chris

  reply	other threads:[~2009-06-04 12:43 UTC|newest]

Thread overview: 67+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-04-27  3:33 Data Deduplication with the help of an online filesystem check Thomas Glanzmann
2009-04-27 13:37 ` Chris Mason
2009-04-28  5:22   ` Thomas Glanzmann
2009-04-28 10:02     ` Chris Mason
2009-04-28 13:49       ` Andrey Kuzmin
2009-04-28 13:58         ` Chris Mason
2009-04-28 14:04           ` Thomas Glanzmann
2009-04-28 17:21             ` Chris Mason
2009-04-28 20:10               ` Thomas Glanzmann
2009-04-28 20:29                 ` Thomas Glanzmann
2009-04-28 13:58         ` jim owens
2009-04-28 16:10       ` Anthony Roberts
2009-04-28 15:59   ` Thomas Glanzmann
2009-04-28 16:04     ` Tomasz Chmielewski
2009-04-28 17:29       ` Edward Shishkin
2009-04-28 17:34         ` Thomas Glanzmann
2009-04-28 17:38           ` Chris Mason
2009-04-28 17:43             ` Thomas Glanzmann
2009-04-28 17:45             ` Heinz-Josef Claes
2009-04-28 20:16               ` Thomas Glanzmann
2009-04-28 20:36                 ` Heinz-Josef Claes
2009-04-28 20:52                   ` Thomas Glanzmann
2009-04-28 20:58                     ` Chris Mason
2009-04-28 21:12                       ` Thomas Glanzmann
2009-04-28 21:26                         ` Chris Mason
2009-04-28 22:14                           ` Thomas Glanzmann
2009-04-28 23:18                             ` Chris Mason
2009-04-29 12:03                               ` Thomas Glanzmann
2009-04-29 13:11                                 ` Michael Tharp
2009-04-29 13:14                                 ` Chris Mason
2009-04-29 13:58                                   ` Thomas Glanzmann
2009-04-29 14:31                                     ` Chris Mason
2009-04-29 15:26                                       ` Thomas Glanzmann
2009-04-29 15:45                                         ` Chris Mason
2009-06-04  8:49                                           ` Thomas Glanzmann
2009-06-04 11:43                                             ` Chris Mason
2009-06-04 12:03                                               ` Thomas Glanzmann
2009-06-04 12:43                                                 ` Chris Mason [this message]
2009-06-05 12:20                                               ` Tomasz Chmielewski
2009-06-05 12:50                                                 ` Chris Mason
2009-06-05 15:35                                                   ` Tomasz Chmielewski
2009-04-29  0:06                       ` Bron Gondwana
2009-05-06 15:16               ` Sander
2009-04-28 17:32       ` Thomas Glanzmann
2009-04-28 17:41         ` Michael Tharp
2009-04-28 20:14           ` Thomas Glanzmann
2009-05-04 14:29           ` Ric Wheeler
2009-05-04 14:39             ` Tomasz Chmielewski
2009-05-04 14:45               ` Ric Wheeler
2009-05-04 15:15                 ` Thomas Glanzmann
2009-05-04 16:03                   ` Ric Wheeler
2009-05-04 16:16                     ` Andrey Kuzmin
2009-05-04 16:24                       ` Thomas Glanzmann
2009-05-04 18:06                         ` Jan-Frode Myklebust
2009-05-04 19:16                           ` Andrey Kuzmin
2009-05-05  8:02                           ` Thomas Glanzmann
2009-05-04 16:26                     ` Thomas Glanzmann
2009-05-04 19:11                       ` Heinz-Josef Claes
2009-05-04 21:29                         ` Dmitri Nikulin
2009-05-05  7:18                           ` Heinz-Josef Claes
2009-05-24  7:27                         ` Thomas Glanzmann
2009-04-28 17:23     ` Chris Mason
2009-04-28 17:37       ` Thomas Glanzmann
2009-04-28 17:43         ` Chris Mason
2009-04-28 20:15           ` Thomas Glanzmann
2009-04-28 21:19           ` Dmitri Nikulin
2009-04-28 20:24       ` Thomas Glanzmann

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