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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Alexander Best <arundel@freebsd.org>
References: <201009161742.24228.tijl@coosemans.org>
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	<20101018155944.GA12425@freebsd.org>
Date: Thu, 21 Oct 2010 13:57:56 +0200
In-Reply-To: <20101018155944.GA12425@freebsd.org> (Alexander Best's message of
	"Mon, 18 Oct 2010 15:59:44 +0000")
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Cc: freebsd-hackers@freebsd.org, mav@freebsd.org,
	Tijl Coosemans <tijl@coosemans.org>, Oliver Fromme <olli@lurza.secnetix.de>
Subject: Re: Summary: Re: Spin down HDD after disk sync or before power off
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Alexander Best <arundel@freebsd.org> writes:
> since there seems no way to distinguish between these two states in ATA(4=
) it's
> probably better to leave it as it is, since doing spin downs upon reboot =
might
> be even worse than not doing spindowns upon shutdown.

No.  Where did you get that idea?  To repeat what I've said before -
several times - in this thread, a modern disk drive can handle hundreds
of thousands of controlled unloads but only a few hundred emergency
unloads. Given the choice between "never spin down" and "always spin
down", the safe alternative is "always spin down".

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no