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Date: Fri, 6 Mar 2009 15:47:38 -0600
From: "Rick C. Petty" <rick-freebsd2008@kiwi-computer.com>
To: Octavian Covalschi <octavian.covalschi@gmail.com>
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Subject: Re: Spin down HDD after disk sync or before power off
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On Fri, Mar 06, 2009 at 03:30:14PM -0600, Octavian Covalschi wrote:
> Why is spinning down is bad for HDD ? I believe it's better to spindown a
> drive,
> instead of cutting power too sudden.

Comparing those two, I'd say it shouldn't matter (although probably a
forced spindown may be better).  But pulling power from a drive does not
mean the drive immediately stops doing stuff.

I was just saying spindown on disks is bad in the first place.  Sure, you
might save some wear and tear on the bearings, but you risk problems with
the heads on both spindown and spinup.  In other words, if you can avoid
power-cycling your drives, they should last longer (in that you're less
likely to destroy the heads).

-- Rick C. Petty