From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jens Axboe <jens.axboe@oracle.com>
Subject: Re: [PATCH 2/2] libata: turn off NCQ if queue depth is adjusted to 1
Date: Wed, 4 Oct 2006 15:37:55 +0200
Message-ID: <20061004133755.GP7778@kernel.dk>
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To: saeed bishara <saeed.bishara@gmail.com>
Cc: Tejun Heo <htejun@gmail.com>, Ric Wheeler <ric@emc.com>, Alan Cox <alan@lxorguk.ukuu.org.uk>, Jeff Garzik <jgarzik@pobox.com>, linux-ide@vger.kernel.org

On Wed, Oct 04 2006, saeed bishara wrote:
> the NCQ commands contain the FUA (force unit access) field
> (mandatory), so disabling the NCQ will waste this feature.
> I don't know how much ans when this feature is usuable, but someday it
> can be usefull.

It's already useful, for io barriers. Yet another reason why the
distinction between depth == 1 and NCQ needs to available.

-- 
Jens Axboe