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From: "Holger Hoffstätte" <holger@applied-asynchrony.com>
To: "Chris Murphy" <lists@colorremedies.com>,
	"Swâmi Petaramesh" <swami@petaramesh.org>
Cc: Btrfs BTRFS <linux-btrfs@vger.kernel.org>
Subject: Re: duperemove : some real world figures on BTRFS deduplication
Date: Fri, 9 Dec 2016 17:07:58 +0100	[thread overview]
Message-ID: <584AD6DE.3080500@applied-asynchrony.com> (raw)
In-Reply-To: <CAJCQCtRgFp6aMRBR8K6PKknGCyC6cxm80tG5xRq8O5hS31pzhA@mail.gmail.com>

On 12/09/16 16:43, Chris Murphy wrote:
>> If compression has nothing to do with this, then this is heavy
>> fragmentation.
> 
> It's probably not that fragmented. Due to compression, metadata
> describes 128KiB extents even though the data is actually contiguous.
> 
> And it might be the same thing in my case also, even though no
> compression is involved.

In that case you can quickly collapse physically contiguous ranges by
reflink-mv'ing (ie. a recent mv) the file across subvolume boundaries
and back. :)

-h


  reply	other threads:[~2016-12-09 16:08 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-12-08 15:11 duperemove : some real world figures on BTRFS deduplication Swâmi Petaramesh
2016-12-08 15:42 ` Austin S. Hemmelgarn
2016-12-08 18:00   ` Timofey Titovets
2016-12-08 20:07   ` Jeff Mahoney
2016-12-08 20:46     ` Austin S. Hemmelgarn
2016-12-08 20:07 ` Jeff Mahoney
2016-12-09 14:06   ` Swâmi Petaramesh
2016-12-09  2:58 ` Chris Murphy
2016-12-09 13:45   ` Swâmi Petaramesh
2016-12-09 15:43     ` Chris Murphy
2016-12-09 16:07       ` Holger Hoffstätte [this message]
     [not found] ` <CAEtw4r2Q3pz8FQrKgij_fWTBw7p2YRB6DqYrXzoOZ-g0htiKAw@mail.gmail.com>
2016-12-09  7:56   ` Peter Becker

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