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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: RW <rwmaillists@googlemail.com>
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Date: Thu, 21 Oct 2010 16:51:26 +0200
In-Reply-To: <20101021145831.7421d4fc@gumby.homeunix.com> (RW's message of
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Summary: Re: Spin down HDD after disk sync or before power off
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RW <rwmaillists@googlemail.com> writes:
> Alexander Best <arundel@freebsd.org> wrote:
> > this seems to indicate that spinning down a disk has quite an impact.
> That's mostly likely a hang-over from older disk technologies when the
> heads touched the surface on spinning down.=20=20

They still do, although these days the "landing zone" has a special
surface designed to minimize friction on the head and prevent it from
sticking to the surface.  In addition, in an emergency unload (when
power is lost while the disk is still spinning) the heads retract in a
violent and uncontrolled manner, which can lead to mechanical damage to
the arms.

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