From owner-freebsd-questions@FreeBSD.ORG Wed Jan 26 20:03:29 2005 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 8335616A4CE for ; Wed, 26 Jan 2005 20:03:29 +0000 (GMT) Received: from obsecurity.dyndns.org (CPE0050040655c8-CM00111ae02aac.cpe.net.cable.rogers.com [69.199.47.57]) by mx1.FreeBSD.org (Postfix) with ESMTP id E1BB743D39 for ; Wed, 26 Jan 2005 20:03:28 +0000 (GMT) (envelope-from kris@obsecurity.org) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id 2FD6A538B8; Wed, 26 Jan 2005 12:03:27 -0800 (PST) Date: Wed, 26 Jan 2005 12:03:26 -0800 From: Kris Kennaway To: "Terry R. Friedrichsen" Message-ID: <20050126200326.GF11116@xor.obsecurity.org> References: <200501261942.j0QJglic043045@uplift.hosp.misyshealthcare.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="K/NRh952CO+2tg14" Content-Disposition: inline In-Reply-To: <200501261942.j0QJglic043045@uplift.hosp.misyshealthcare.com> User-Agent: Mutt/1.4.2.1i cc: linicks@gmail.com cc: freebsd-questions@freebsd.org Subject: Re: FreeBSD 5.3 file system troubles X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 26 Jan 2005 20:03:29 -0000 --K/NRh952CO+2tg14 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Jan 26, 2005 at 12:42:47PM -0700, Terry R. Friedrichsen wrote: >=20 > Thanks for responding to my inquiry. If it fits into your testing progra= m, > try running something that works the file system and simply turn off the > system power in the middle of it. This is expected if you don't turn off write caching of the hard disks. It breaks the softupdates consistency model because data written to the disk may not actually be written to the disk, so it's not there following an unexpected power cycle. Unfortunately write caching causes a performance hit, and there was a large user backlash when it was briefly enabled by default some years ago. Kris --K/NRh952CO+2tg14 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.0 (FreeBSD) iD4DBQFB9/eOWry0BWjoQKURAu+MAJUTsENY3WQzuPrbTOlvc5UfQoeOAJ9XCm6j hjsQ3Xz9k8I2nZzEIMLmDw== =UsBY -----END PGP SIGNATURE----- --K/NRh952CO+2tg14--