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From: Garrett Cooper <gcooper@FreeBSD.org>
To: Chuck Swiger <cswiger@mac.com>
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Cc: Alexander Best <arundel@freebsd.org>, freebsd-current@freebsd.org
Subject: Re: two ata write chaching request
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On Mon, Dec 20, 2010 at 3:29 PM, Chuck Swiger <cswiger@mac.com> wrote:
> On Dec 20, 2010, at 3:10 PM, Alexander Best wrote:
>> 1) write caching to be turned on and off for individual hdds
>> =A0 (i.e. hw.ata.X.wc) and
>> 2) to be able to turn write chaching on and off on the fly.
>
> NetBSD's dkctl allows one to enable and disable read or write caches on a=
 per-device basis, on the fly. =A0Presumably atacontrol or whatever the new=
 ada / ACHI driver uses for control would be the FreeBSD equivalent....

    atacontrol doesn't work with ahci. Some changes to this code
should be coming soon, so I don't advise investing too much in hacking
the driver for this support (unless you talk to mav@ first)...
Thanks,
-Garrett