From owner-freebsd-current@FreeBSD.ORG Mon Dec 19 23:22:18 2011 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 78EB4106564A for ; Mon, 19 Dec 2011 23:22:18 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from qmta05.westchester.pa.mail.comcast.net (qmta05.westchester.pa.mail.comcast.net [76.96.62.48]) by mx1.freebsd.org (Postfix) with ESMTP id 37ACF8FC08 for ; Mon, 19 Dec 2011 23:22:18 +0000 (UTC) Received: from omta15.westchester.pa.mail.comcast.net ([76.96.62.87]) by qmta05.westchester.pa.mail.comcast.net with comcast id B65L1i0011swQuc55BNJDr; Mon, 19 Dec 2011 23:22:18 +0000 Received: from koitsu.dyndns.org ([67.180.84.87]) by omta15.westchester.pa.mail.comcast.net with comcast id BBNH1i01B1t3BNj3bBNJAQ; Mon, 19 Dec 2011 23:22:18 +0000 Received: by icarus.home.lan (Postfix, from userid 1000) id 65077102C19; Mon, 19 Dec 2011 15:22:16 -0800 (PST) Date: Mon, 19 Dec 2011 15:22:16 -0800 From: Jeremy Chadwick To: Alexander Best Message-ID: <20111219232216.GA31865@icarus.home.lan> References: <20111219224700.GA75581@freebsd.org> <32197.1324334968@critter.freebsd.dk> <20111219225633.GA77147@freebsd.org> <20111219232010.GA31612@icarus.home.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20111219232010.GA31612@icarus.home.lan> User-Agent: Mutt/1.5.21 (2010-09-15) X-Mailman-Approved-At: Mon, 19 Dec 2011 23:47:05 +0000 Cc: freebsd-fs@freebsd.org, Poul-Henning Kamp , freebsd-current@freebsd.org Subject: Re: can a wrong alignment cause a decrease in a hdd's life expectancy? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 19 Dec 2011 23:22:18 -0000 On Mon, Dec 19, 2011 at 03:20:10PM -0800, Jeremy Chadwick wrote: > On Mon, Dec 19, 2011 at 10:56:33PM +0000, Alexander Best wrote: > > On Mon Dec 19 11, Poul-Henning Kamp wrote: > > > In message <20111219224700.GA75581@freebsd.org>, Alexander Best writes: > > > >On Mon Dec 19 11, Poul-Henning Kamp wrote: > > > >> In message <20111219221617.GA70383@freebsd.org>, Alexander Best writes: > > > >> > > > >> >ps: the hdd only gets mounted read-only! > > > >> > > > >> There is no known wear-effects in flash storage as long as you > > > >> only read. > > > >> > > > >> You may need to do refresh-writes every 5-10 years to avoid > > > >> tunnel-leakage bit errors, but most flash controllers use semi-long > > > >> ECC syndromes and will do so on first bit that gives an read error. > > > > > > > >this is a regular hdd i believe -- no ssd. at least when i plug it into my > > > >usb drive i hear the hdd spinning up and causing vibrations. i don't think > > > >that would be the case with an ssd. > > > > > > Ahh, sorry, I don't know why I thought it was flash. > > > > no problem. so will the improper alignment also not cause a life expectancy > > shortage in case of a hdd (non-flash-based)? > > The improper alignment will result in sub-par write performance, and a > slight decrease in read performance writes -- but will not impact life > expectancy or "harm" the drive in any way. This should have read "...slight decrease in read performance", not "read performance writes". Editing mistake on my part. :-) -- | Jeremy Chadwick jdc at parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, US | | Making life hard for others since 1977. PGP 4BD6C0CB |