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From: Mike Fleetwood <mike.fleetwood@googlemail.com>
Date: Mon, 12 Sep 2016 22:32:27 +0100
Message-ID: <CAMU1PDgonwcpAtxPhOBQkoaGk8ev++GbL3p_JRAKB+FXKo0sTw@mail.gmail.com>
Subject: Re: Small fs
To: linux-btrfs <linux-btrfs@vger.kernel.org>
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On 12 September 2016 at 19:55, Austin S. Hemmelgarn
<ahferroin7@gmail.com> wrote:
> I'm not sure about gparted, but the default behavior for mkfs is as follows:
> 1. Is the device rotational? (check /sys/block/<device>/rotational).  If
> not, do some extra stuff to try and ID it as an SSD.  If it is an SSD, use
> SINGLE mode for metadata, otherwise use DUP mode for metadata.
> 2. Is the FS set for mixed-bg?  If so, use the same profile for data as
> metadata, otherwise use SINGLE mode for data.
>
> It would not surprise me if gparted switches to single metadata mode for a
> small enough FS, but I'm not certain.  I do think that they just use the
> default selection for mixed-bg though, which means not using it in current
> btrfs-progs versions.

GParted always just takes the mkfs.btrfs defaults.

https://git.gnome.org/browse/gparted/tree/src/btrfs.cc?h=GPARTED_0_26_1#n154