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Message-ID: <170fa0d20805161255i31d768ceh3b15c2640f06524b@mail.gmail.com>
Date: Fri, 16 May 2008 15:55:30 -0400
From: "Mike Snitzer" <snitzer@gmail.com>
To: "device-mapper development" <dm-devel@redhat.com>, agk@redhat.com,
       "Ric Wheeler" <ric@emc.com>, "Michael Tokarev" <mjt@tls.msk.ru>,
       "Andi Kleen" <andi@firstfloor.org>, linux-kernel@vger.kernel.org
Subject: Re: [dm-devel] Re: [PATCH] Implement barrier support for single device DM devices
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On Mon, Feb 18, 2008 at 10:45 PM, Alasdair G Kergon <agk@redhat.com> wrote:
> On Mon, Feb 18, 2008 at 08:52:10AM -0500, Ric Wheeler wrote:
>  > I understand that. Most of the time, dm or md devices are composed of
>  > uniform components which will uniformly support (or not) the cache flush
>  > commands used by barriers.
>
>  As a dm developer, it's "almost none of the time" because trivial
>  configurations aren't the ones that require lots of testing effort.
>
>  Let's stop arguing over "most of the time":-)
>
>  As Andi points out, there are certainly enough real-world users of
>  "single linear or crypt target using one physical device" for it to be
>  worth our supporting it.

Hi Alasdair,

Given that you feel supporting barriers on single device DM targets is
a good thing, what is the status of such support (like Andi's patch)
making it upstream?

Mike