From: Roman Mamedov <rm@romanrm.net>
To: Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc: Dave Chinner <david@fromorbit.com>, linux-btrfs@vger.kernel.org
Subject: Re: Unexpected reflink/subvol snapshot behaviour
Date: Sat, 23 Jan 2021 15:39:33 +0500 [thread overview]
Message-ID: <20210123153933.534a43ea@natsu> (raw)
In-Reply-To: <58c9d792-5af4-7b54-2072-77230658e677@gmx.com>
On Sat, 23 Jan 2021 16:42:33 +0800
Qu Wenruo <quwenruo.btrfs@gmx.com> wrote:
> For the worst case, btrfs can allocate a 128 MiB file extent, and have
> good luck to write 127MiB into the extent. It will take 127MiB + 128MiB
> space, until the last 1MiB of the original extent get freed, the full
> 128MiB can be freed.
Does it mean enabling compression actually mitigates this issue as a
side-effect? Since each extent will be limited to only 128K.
What are the typical extent sizes without compression?
--
With respect,
Roman
next prev parent reply other threads:[~2021-01-23 10:40 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-21 22:20 Unexpected reflink/subvol snapshot behaviour Dave Chinner
2021-01-23 8:42 ` Qu Wenruo
2021-01-23 8:51 ` Qu Wenruo
2021-01-23 10:39 ` Roman Mamedov [this message]
2021-01-23 10:58 ` Qu Wenruo
2021-01-24 13:08 ` Filipe Manana
2021-01-24 22:36 ` Dave Chinner
2021-01-25 1:09 ` Qu Wenruo
2021-01-29 23:25 ` Zygo Blaxell
2021-02-02 0:13 ` Dave Chinner
2021-02-12 3:04 ` Zygo Blaxell
2021-01-24 0:19 ` Zygo Blaxell
2021-01-24 21:43 ` Dave Chinner
2021-01-30 1:03 ` Zygo Blaxell
2021-02-02 2:14 ` Darrick J. Wong
2021-02-02 6:02 ` Dave Chinner
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