From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Liontooth Subject: Re: Hard drive lifetime: wear from spinning up or rebooting vs running Date: Mon, 06 Feb 2006 08:45:41 -0800 Message-ID: <43E77D35.1040905@cogweb.net> References: <43E68D62.4080704@cogweb.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Mattias Wadenstein wrote: > On Sun, 5 Feb 2006, David Liontooth wrote: > >> In designing an archival system, we're trying to find data on when i= t >> pays to power or spin the drives down versus keeping them running. > > Hitachi claims "5 years (Surface temperature of HDA is 45=B0C or less= ) > Life of the drive does not change in the case that the drive is used > intermittently." for their ultrastar 10K300 drives. I suspect that th= e > best estimates you're going to get is from the manufacturers, if you > can find the right documents (OEM specifications, not marketing blurb= s). "Intermittent" may assume the drive is powered on and in regular use an= d may simply be a claim that spindle drive components are designed to fai= l simultaneously with disk platter and head motor components.=20 Konstantin's observation that "disk die about evenly from 3 causes: no spinning (dead spindle motor power electronics), heads do not move (dea= d head motor power electronics), or spontaneusly developing bad sectors (disk platter contamination?)" is consistent with a rational goal of manufacturing components with similar lifetimes under normal use.=20 > For their deskstar (sata/pata) drives I didn't find life time > estimates beyond 50000 start-stop-cycles. If components are in fact manufactured to fail simultaneously under normal use (including a dozen or two start-stop cycles a day), then taking the drive off-line for more than a few hours should unproblematically extend its life. Appreciate all the good advice and references. While we have to rely on specifications rather than actual long-term tests, this should still move us in the right direction. One of the problems with creating a digital archive is that the technology has no archival history. We know acid-free paper lasts millennia; how long do modern hard drives last in cold storage? To some people's horror, we now know home-made CDs last = a couple of years. Dave - To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html