From owner-freebsd-current@FreeBSD.ORG Fri Jun 9 06:53:26 2006 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 7048916A41A; Fri, 9 Jun 2006 06:53:26 +0000 (UTC) (envelope-from wb@freebie.xs4all.nl) Received: from smtp-vbr16.xs4all.nl (smtp-vbr16.xs4all.nl [194.109.24.36]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9CD6043D78; Fri, 9 Jun 2006 06:53:25 +0000 (GMT) (envelope-from wb@freebie.xs4all.nl) Received: from freebie.xs4all.nl (freebie.xs4all.nl [213.84.32.253]) by smtp-vbr16.xs4all.nl (8.13.6/8.13.6) with ESMTP id k596rCDD005120; Fri, 9 Jun 2006 08:53:20 +0200 (CEST) (envelope-from wb@freebie.xs4all.nl) Received: from freebie.xs4all.nl (localhost [127.0.0.1]) by freebie.xs4all.nl (8.13.6/8.13.3) with ESMTP id k596rCVl004346; Fri, 9 Jun 2006 08:53:12 +0200 (CEST) (envelope-from wb@freebie.xs4all.nl) Received: (from wb@localhost) by freebie.xs4all.nl (8.13.6/8.13.6/Submit) id k596rBCX004345; Fri, 9 Jun 2006 08:53:11 +0200 (CEST) (envelope-from wb) Date: Fri, 9 Jun 2006 08:53:11 +0200 From: Wilko Bulte To: "Daniel O'Connor" Message-ID: <20060609065311.GB4251@freebie.xs4all.nl> References: <20060608132048.GD86198@garage.freebsd.pl> <20060608174113.GC1075@roadrunner.q.local> <200606091215.41787.doconnor@gsoft.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200606091215.41787.doconnor@gsoft.com.au> User-Agent: Mutt/1.5.11 X-Virus-Scanned: by XS4ALL Virus Scanner Cc: freebsd-current@freebsd.org, Pawel Jakub Dawidek Subject: Re: Data authentication for geli(8) committed to HEAD. 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: Fri, 09 Jun 2006 06:53:26 -0000 On Fri, Jun 09, 2006 at 12:15:33PM +0930, Daniel O'Connor wrote.. > On Friday 09 June 2006 03:11, Ulrich Spoerlein wrote: > > I have an external HDD that I initially attached via Firewire, but I've > > since switched to USB, as our firewire subsystem is less than rock > > Interesting. I find the reverse :) > Then again I started using Firewire in 4.x where USB2.0 didn't exist and the > USB 1 code was kind of dodgy. > > > The question really is, are 512 byte disk writes considered to be some > > kind of "atomic" as it is the smallest disk block size? What does the > > ATA subsystem do with writes of 4096? Are they completed atomically too, > > or not? > > I think that in reality with a modern high capacity disk you don't get atomic > writes at all because they all re-write whole tracks. > > Yes this violates the assumption soft updates makes, I believe the only way > around it is to buy SCSI drives (not because they're SCSI per se, but because > they're smaller capacity so they don't do this) Don't tell my 300GB SCSI disks (at work) that they are 'small'. -- Wilko Bulte wilko@FreeBSD.org