From owner-freebsd-hackers@FreeBSD.ORG Thu Jul 27 20:58:53 2006 Return-Path: X-Original-To: freebsd-hackers@freebsd.org Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9489A16A4E1 for ; Thu, 27 Jul 2006 20:58:53 +0000 (UTC) (envelope-from mwm-keyword-freebsdhackers2.e313df@mired.org) Received: from mired.org (vpn.mired.org [66.92.153.74]) by mx1.FreeBSD.org (Postfix) with SMTP id B9A9643D49 for ; Thu, 27 Jul 2006 20:58:52 +0000 (GMT) (envelope-from mwm-keyword-freebsdhackers2.e313df@mired.org) Received: (qmail 51647 invoked by uid 1001); 27 Jul 2006 20:58:51 -0000 Received: by bhuda.mired.org (tmda-sendmail, from uid 1001); Thu, 27 Jul 2006 16:58:51 -0400 (EDT) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <17609.10507.322936.614793@bhuda.mired.org> Date: Thu, 27 Jul 2006 16:58:51 -0400 To: Andreas Klemm In-Reply-To: <20060727202105.GA14724@titan.klemm.apsfilter.org> References: <20060727063936.GA1246@titan.klemm.apsfilter.org> <20060727122159.GB4217@britannica.bec.de> <20060727134948.GA3755@energistic.com> <20060727180412.GB48057@megan.kiwi-computer.com> <17609.1474.618423.970137@bhuda.mired.org> <20060727202105.GA14724@titan.klemm.apsfilter.org> X-Mailer: VM 7.17 under 21.4 (patch 19) "Constant Variable" XEmacs Lucid X-Primary-Address: mwm@mired.org X-face: "5Mnwy%?j>IIV\)A=):rjWL~NB2aH[}Yq8Z=u~vJ`"(,&SiLvbbz2W`; h9L,Yg`+vb1>RG% *h+%X^n0EZd>TM8_IB;a8F?(Fb"lw'IgCoyM.[Lg#r\ X-Delivery-Agent: TMDA/1.0.3 (Seattle Slew) From: Mike Meyer Cc: freebsd-hackers@freebsd.org Subject: Re: disklabel differences FreeBSD, DragonFly 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: Thu, 27 Jul 2006 20:58:53 -0000 In <20060727202105.GA14724@titan.klemm.apsfilter.org>, Andreas Klemm typed: > On Thu, Jul 27, 2006 at 02:28:18PM -0400, Mike Meyer wrote: > > These days, the only technical reason I know of for having separate > > mountpoints is because you want to run commands that work on > > filesystems on the two parts with different arguments or under > > different conditions. > Well I still prefer to "design" my filesystems no matter how big > disks are. Yes, and most of those qualify as needing to "run commands that workon filesystems on the two parts with different arguments ...". > Also I'd gues that its still valid that less file movement > in root filesystem increases robustness if you have a power outage. > Same true for other important filesystems. Actually, it one of the FS gurus convincing me that this was no longer true that converted me to the idea that reducing the file system count was a good idea. What you say was certainly true for 4.2BSD, but when was the last time you saw an entire file system toasted when something failed hard? Or even significant damage to files that weren't actually in transit at the time? I know the last time it happened to me - it was over a decade ago. I had a desktop Solaris box I'd set up as web server because the IT department was a typical IT department. So it wasn't on batteries like every other server in the place. We took a power hit, and it crashed hard. Power came back, and it started fsck'ing it's file system. Partway through that we got a *second* power hit, so it crashed hard in the middle of fsck'ing. This power outage lasted long enough that the backup generators kicked in, so it came back up and started fsck'ing again. At which piont the backup generators cut out, because they hadn't been refueled after the last outage. So it crashed hard *again* in the middle of fsck'ing the file system. The file system was unrecoverable. > Also it makes it easier to upgrade a system, since you only nail > / and /usr, if the rest is in other filesystems. > > Also its easier to newfs "/" and "/usr", if "/var", "/usr/local" > and "/usr/X11R6", "/home", ... are on differnet filesystems. Right. I typically install / and /usr as distinct files systems for just that reason (/ and /usr have different backup & recovery strategies and I use dump, so that's why they are two partitions). So why does / need to be different from /var, /usr different from /usr/X11R6 and /home different from /usr/local? Seriously now - what I just described is my typical install. > You see, I think there is still demand for using many filesystems > if you are open minded for having the best support in every "shitty" > situation ;-) Well, there are always special cases. But hardware is so cheap these days, I'm used to fine-tuning the *system*, not just the partition. If something is so critical that it needs it's own partition, it's probably so critical that it needs it's own system as well. In fact, most of the thing I work on these days are so critical that they need several systems, half of them at a second site with automatic failover between them. http://www.mired.org/consulting.html Independent Network/Unix/Perforce consultant, email for more information.