From: Tomasz Pala <gotar@polanet.pl>
To: "Austin S. Hemmelgarn" <ahferroin7@gmail.com>
Cc: Niccol?? Belli <darkbasic@linuxsystems.it>,
David Sterba <dsterba@suse.cz>,
linux-btrfs@vger.kernel.org
Subject: Re: Any chance to get snapshot-aware defragmentation?
Date: Sat, 19 May 2018 01:55:30 +0200 [thread overview]
Message-ID: <20180518235530.GA12463@polanet.pl> (raw)
In-Reply-To: <de7adf73-ba0b-9154-e3d1-b4e468ad3c96@gmail.com>
On Fri, May 18, 2018 at 13:10:02 -0400, Austin S. Hemmelgarn wrote:
> Personally though, I think the biggest issue with what was done was not
> the memory consumption, but the fact that there was no switch to turn it
> on or off. Making defrag unconditionally snapshot aware removes one of
> the easiest ways to forcibly unshare data without otherwise altering the
The "defrag only not-snapshotted data" mode would be enough for many
use cases and wouldn't require more RAM. One could run this before
taking a snapshot and merge _at least_ the new data.
And even with current approach it should be possible to interlace
defragmentation with some kind of naive-deduplication; "naive" in the
approach of comparing blocks only within the same in-subvolume paths.
--
Tomasz Pala <gotar@pld-linux.org>
next prev parent reply other threads:[~2018-05-19 0:12 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-11 15:22 Any chance to get snapshot-aware defragmentation? Niccolò Belli
2018-05-18 16:20 ` David Sterba
2018-05-18 16:36 ` Niccolò Belli
2018-05-18 17:10 ` Austin S. Hemmelgarn
2018-05-18 17:18 ` Niccolò Belli
2018-05-18 18:33 ` Austin S. Hemmelgarn
2018-05-18 22:26 ` Chris Murphy
2018-05-18 22:46 ` Omar Sandoval
2018-05-19 8:54 ` Niccolò Belli
2018-05-21 13:15 ` Austin S. Hemmelgarn
2018-05-21 13:42 ` Timofey Titovets
2018-05-21 15:38 ` Austin S. Hemmelgarn
2018-06-01 3:19 ` Zygo Blaxell
2018-05-18 23:55 ` Tomasz Pala [this message]
2018-05-19 8:56 ` Niccolò Belli
[not found] ` <20180520105928.GA17117@polanet.pl>
2018-05-21 13:49 ` Niccolò Belli
2018-05-21 17:43 ` David Sterba
2018-05-21 19:22 ` Austin S. Hemmelgarn
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