From owner-freebsd-hackers@FreeBSD.ORG Fri Jun 15 11:50:22 2007 Return-Path: X-Original-To: freebsd-hackers@freebsd.org Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id E277416A400 for ; Fri, 15 Jun 2007 11:50:22 +0000 (UTC) (envelope-from peterjeremy@optushome.com.au) Received: from turion.vk2pj.dyndns.org (c220-239-20-82.belrs4.nsw.optusnet.com.au [220.239.20.82]) by mx1.freebsd.org (Postfix) with ESMTP id 6D2BF13C458 for ; Fri, 15 Jun 2007 11:50:22 +0000 (UTC) (envelope-from peterjeremy@optushome.com.au) Received: from turion.vk2pj.dyndns.org (localhost.vk2pj.dyndns.org [127.0.0.1]) by turion.vk2pj.dyndns.org (8.14.1/8.14.1) with ESMTP id l5FBoLuu001998; Fri, 15 Jun 2007 21:50:21 +1000 (EST) (envelope-from peter@turion.vk2pj.dyndns.org) Received: (from peter@localhost) by turion.vk2pj.dyndns.org (8.14.1/8.14.1/Submit) id l5FBoLIo001997; Fri, 15 Jun 2007 21:50:21 +1000 (EST) (envelope-from peter) Date: Fri, 15 Jun 2007 21:50:20 +1000 From: Peter Jeremy To: Jeremy Chadwick Message-ID: <20070615115020.GG1173@turion.vk2pj.dyndns.org> References: <4670B27B.6060606@digitalstratum.com> <20070614040848.GA30741@eos.sc1.parodius.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="VrqPEDrXMn8OVzN4" Content-Disposition: inline In-Reply-To: <20070614040848.GA30741@eos.sc1.parodius.com> X-PGP-Key: http://members.optusnet.com.au/peterjeremy/pubkey.asc User-Agent: Mutt/1.5.15 (2007-04-06) Cc: freebsd-hackers@freebsd.org Subject: Re: Disk block or sector to file mapping? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 15 Jun 2007 11:50:23 -0000 --VrqPEDrXMn8OVzN4 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 2007-Jun-13 21:08:48 -0700, Jeremy Chadwick wrote: >Realistically, what we need on FreeBSD is a tool similar to Solaris's >format(8) "analyze" command, which does a raw disk scan (r, r/w, and a >couple other operations). The "analyze" function is just a pattern test with the ability to restore the original content. Writing one is trivial. >[1] - If the OS is seeing bad blocks on a PATA/SATA disk, usually it means >that the internal remapping table is full, which means that there were >other bad blocks on the disk which it has silently remapped for you to >avoid pain -- and space for those blocks has been exhausted. Re-mapping generally only works on writes. If you can't read existing data off the platter then you will get a bad block error irrespective of the remapping table. A sector that could not be read can often be written. >and you're stuck simply replacing the disk entirely. Bad blocks have a >tendency to spread too... Definitely - once the number of soft errors starts increasing, it's time to replace the disk. --=20 Peter Jeremy --VrqPEDrXMn8OVzN4 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (FreeBSD) iD8DBQFGcnz8/opHv/APuIcRAgAvAJ0f+1b7PV2URU337bp24KyHbCCtBwCeMXbv XoTG5RMH++dBvtZR9bTDESY= =bApP -----END PGP SIGNATURE----- --VrqPEDrXMn8OVzN4--