From owner-freebsd-hackers@FreeBSD.ORG Fri Jul 28 00:01:03 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 A41A516A505 for ; Fri, 28 Jul 2006 00:01:03 +0000 (UTC) (envelope-from xfb52@dial.pipex.com) Received: from smtp-out2.blueyonder.co.uk (smtp-out2.blueyonder.co.uk [195.188.213.5]) by mx1.FreeBSD.org (Postfix) with ESMTP id B5E2F43D4C for ; Fri, 28 Jul 2006 00:01:00 +0000 (GMT) (envelope-from xfb52@dial.pipex.com) Received: from [172.23.170.144] (helo=anti-virus03-07) by smtp-out2.blueyonder.co.uk with smtp (Exim 4.52) id 1G6Fmm-0006Bw-3C; Fri, 28 Jul 2006 01:01:00 +0100 Received: from [82.41.35.166] (helo=[192.168.0.2]) by asmtp-out6.blueyonder.co.uk with esmtp (Exim 4.52) id 1G6Fml-0005nC-8v; Fri, 28 Jul 2006 01:00:59 +0100 Message-ID: <44C953BA.4070008@dial.pipex.com> Date: Fri, 28 Jul 2006 01:00:58 +0100 From: Alex Zbyslaw User-Agent: Mozilla/5.0 (X11; U; FreeBSD i386; en-GB; rv:1.7.13) Gecko/20060515 X-Accept-Language: en MIME-Version: 1.0 To: freebsd-hackers@freebsd.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> <44C910BE.9000108@dial.pipex.com> <20060727185721.GC25626@manor.msen.com> <17609.9516.506115.204334@bhuda.mired.org> <44C93454.5020404@dial.pipex.com> <17609.16421.670624.80289@bhuda.mired.org> In-Reply-To: <17609.16421.670624.80289@bhuda.mired.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit 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: Fri, 28 Jul 2006 00:01:03 -0000 Mike Meyer wrote: >>>>A further reason to separate partitions is that dump works at the level >>>>of a partition. Different partitions may have very different backup >>>>requirements, and for those of us without huge tape drives, partitioning >>>>to a size that can be dumped on one tape makes life easier. >>>> >>>> >>>That's one of the technical reasons I mentioned in the part you >>>didn't quote. >>> >>> >>To my mind, it only takes *one* technical reason. If I need multiple >>partitions to make backups easy, then arguments about log files are >>irrelevant :-) >> >> > >If you're going to count 1, 2, many, then we already have "many" >partitions, and don't need more. Once you get into finer distinctions >of "many", you need to figure out which reasons are actually valid, >and which are spurious, so you can pick from among those manys. > > I have no real idea what this means, sorry. It seems to me that whoever made the initial decision to stop at 8 (size of an integer?) clearly thought counting past 2 was worthwhile. Maybe the original reasons no longer apply since quite a lot has changed since then :-) >>>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. >>> >>> >>Not everyone is in a position to throw money at everything and what's >>cheap to you isn't cheap to everyone. >> >> > >Boxes are cheaper than disk space - my last two low-end boxes cost >less than my last small disk drive, even though I ordered them all >about the same time. If you can afford the disk for some process, then >chances are good you can afford a system instead, or as well. > > I don't understand this either. Surely the box has to include the disk space so how can it cost less? If it costs less because it's a cheap piece of junk, why would I even want it? And the "cost" of the system doesn't stop at the up front price - running costs including maintaining the box surely count (not to mention that I have nowhere to put the damn thing). And I'm not sure where needing a separate partition and criticality became the same thing. I don't claim to want or need separate partitions because any particular subset of the filesystem is critical, but because I want it to be separate for at least the two reasons outlined below. >>I can't possibly justify one system for everything that needs a >>partition, nor do I even feel the need to do that. If anything, it >>would be a major inconvenience. >> >> > >My claim is that your "everything that needs a partition" probably >includes things that don't. But to prove that, we need to examine the >reasons you think those things need a partition. I believe the only >one you've given so far - as a space firewall - is specious. > > Except that we also have the "dump", and the "different params for different parts of the filesystem" arguments. I think you agreed that you counted those as technical reasons. >Your arguments remind me of the environments I worked on in the 70s >and 80s. Minis and mainframes that did all the computing for an >organization. All the daemons that talked to the outside world ran on >the same box as the developers ran compiles and tests on, etc. While >that worked really well when it came to generating a robust OS, I >haven't seen an environment like that in decades. Hell, most of my >clients would shit bricks at the thought of putting their source or >data on a machine that could be reached from the internet at large at >all. Every developler has a box - or three - on their desks. The ETL >boxes are distinct from the database boxes are distinct from the >internal mail server is distinct from the external mail server, >etc. If I want to have a process send email notices about something, I >usually have to beat on them if I want a mail server on the box. And >so on.... > > Fine. You have access to lots of money and infrastructure. I don't. Throwing money at a problem is not a solution available to everyone. >>>Frankly, if you're really worried about >>>bootable slices, you should be advocating giving FreeBSD the ability >>>to boot from a logical volume. >>> >>> >>Who said I didn't? I have no objection to such a facility and would >>welcome it. It just imagined that extending the number of partitions >>from 8 to 16 would have been easier than booting from logical slices. >>If booting from logical slices is easier then I'm all for it. >> >> > >You're not asking the right question just yet. The question shouldn't >be "which is easier to add", but "which provides the most benefit for >the least pain" (which subsumes the pain involved in adding it). I >believe that the benefits of adding more partitions per slice are >minimal - there are at least three ways to add more file systems that >aren't bootable, and there's a better fix to the problem of wanting >more bootable partitions - and the pain involved in upgrading a system >across a change in the bsdlabel would be rather high. > > This all sounds fine to me, though the OP who wanted to mount a DragonFly partition might disagree :-( The bottom line for me is this: if the number of partitions per slice were to increase from 8 to 16, that would make my life easier as I do things now. The way I do things now works very well for me. and nothing you have said tells me how I could do things differently and still have it work as well. If no-one is going to increase partitions from 8 to 16, I'll survive. If someone instead makes logical partitions bootable, I'd be happy too. If someone comes up with something completely different that makes it easier for me to boot multiple FreeBSD's on a single machine without a) adding extra disk or b) buying expensive software, I'd be thrilled to bits. >there are at least three ways to add more file systems that >aren't bootable, > Logical partitions. What would be your other two? (Off list, if you prefer and can be bothered to answer, since it has got rather OT). --Alex