Feedback-ID: iac594737:Fastmail
Date:   Tue, 7 Feb 2023 11:24:26 -0500
From:   Demi Marie Obenour <demi@invisiblethingslab.com>
To:     Joe Thornber <thornber@redhat.com>
Cc:     Alasdair Kergon <agk@redhat.com>,
        Mike Snitzer <snitzer@kernel.org>, dm-devel@redhat.com,
        Marek =?utf-8?Q?Marczykowski-G=C3=B3recki?= 
        <marmarek@invisiblethingslab.com>, linux-kernel@vger.kernel.org
Subject: Re: [dm-devel] [PATCH 2/2] dm-thin: Allow specifying an offset
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Date: Tue, 7 Feb 2023 11:24:26 -0500
From: Demi Marie Obenour <demi@invisiblethingslab.com>
To: Joe Thornber <thornber@redhat.com>
Cc: Alasdair Kergon <agk@redhat.com>, Mike Snitzer <snitzer@kernel.org>,
	dm-devel@redhat.com,
	Marek =?utf-8?Q?Marczykowski-G=C3=B3recki?= <marmarek@invisiblethingslab.com>,
	linux-kernel@vger.kernel.org
Subject: Re: [dm-devel] [PATCH 2/2] dm-thin: Allow specifying an offset

On Tue, Feb 07, 2023 at 03:03:57PM +0000, Joe Thornber wrote:
> Nack.  I'm not building a linear target into every other target.  Layering
> targets is simple.

It also introduces a performance penalty, which is measurable on some
workloads.  Even dm-linear is not free.  The crypt target also has this
feature, so there is precedent.
--=20
Sincerely,
Demi Marie Obenour (she/her/hers)
Invisible Things Lab

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