From owner-freebsd-questions@FreeBSD.ORG Mon Feb 5 08:23:24 2007 Return-Path: X-Original-To: questions@freebsd.org Delivered-To: freebsd-questions@FreeBSD.ORG Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 94BCD16A400 for ; Mon, 5 Feb 2007 08:23:24 +0000 (UTC) (envelope-from indigo@voda.cz) Received: from smtp.voda.cz (gw.voda.cz [212.24.154.90]) by mx1.freebsd.org (Postfix) with ESMTP id 258B413C491 for ; Mon, 5 Feb 2007 08:23:23 +0000 (UTC) (envelope-from indigo@voda.cz) Received: from localhost (localhost [127.0.0.1]) by smtp.voda.cz (Postfix) with ESMTP id C21AE43784 for ; Mon, 5 Feb 2007 09:23:22 +0100 (CET) Received: from smtp.voda.cz ([127.0.0.1]) by localhost (mail.voda.cz [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 11562-01 for ; Mon, 5 Feb 2007 09:23:20 +0100 (CET) Received: from spyro.eiecon.net (unknown [213.151.77.190]) by smtp.voda.cz (Postfix) with ESMTP id 92340436E5 for ; Mon, 5 Feb 2007 09:23:20 +0100 (CET) Date: Mon, 05 Feb 2007 09:23:20 +0100 To: "questions@freebsd.org" From: Indigo Content-Type: text/plain; format=flowed; delsp=yes; charset=iso-8859-2 MIME-Version: 1.0 References: Content-Transfer-Encoding: 7bit Message-ID: In-Reply-To: User-Agent: Opera Mail/9.10 (Win32) X-Virus-Scanned: by amavisd-new at voda.cz Cc: Subject: Re: Dumb filesystem idea X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 05 Feb 2007 08:23:24 -0000 > On 2/4/07, Indigo wrote: >> Hello Everyone, >> Im about to try a disklayout experiment and I wanted to ask everyone >> if >> Im trying things that are pointless or if I should extend the experiment >> somehow. >> >> Hardware: >> Highpoint RocketRAID 2320 >> 2xWD Raptor 74GB >> 5xWD Caviar 320GB >> >> Original idea for the setup: >> 74GB RAID1 (Raptors) >> /,/var,/usr >> 50GB RAID0 (Caviars[10GB from each - maybe less]) >> swap,/usr/obj,/tmp,[/var/audit] >> 1TB+ RAID5 (Caviars[the rest]) >> /home (or just general storage) >> >> The goal is to waste as few fast/reliable space as possible on things >> that >> CAN be lost and to generally reorganize the filesystem by file purpose. > > It looks to me like you are wasting system drive channels. That is, > IDE can only have two drives per channel, SATA can have one drive per > channel. SCSI is too expensive to waste on 10GB drives. So while you > might be moving low-use data off of a high-use file system you are > losing the ability to have a high-capacicy file system. > >> Known issue is that I'll need some script to recreate the RAID0 >> filesystems when they crash. > > Shouldn't be a prolem with gvinum. Except that some applications > /will/ crash if /tmp dissipears, and you certainly don't want swap to > dissipear if it's being used either. > >> Am I onto something here? I feel like running in circles - it's dumb to >> put /var/obj on the RAID1 where it just eats valuable space. But it's >> also >> dumb to put things on a RAID0 where they will crash a running system in >> the event of disk failure. I know my idea won't work but I wanted to ask >> if anyone was playing with similar ideas. > > The trick is to balance your performance requirements and your fault > tolerance with the data usage and system security requirements. The > fault tolerance of RAID 1 and RAID 5 are nearly the same, each can > survice exactly one drive failure. In your example above, the Raptor's > are fast, but depending on what the system is used for you might need > that speed in /var, swap, or some other mount point, most of the time > IO on / and /usr is pretty low. On the other hard, RAID 5 is fine for > a file server, but if you have a database on that volume you might > want to go with RAID 10. > > So no, your idea isn't dumb, you just didn't give enough information > to make a meaningful assessment. > Some more detail then: The HighPoint card is very decent, it can make the whole setup I described appear as three SCSI disks (da0-2). Ill make one slice on each and then partition those slices as I described. So FreeBSD will only see 3 SCSI disks(74GB,50GB,1TB) it shouldn't see the original SATA disks like it does with on-board controllers. da0s1a / da0s1d /var [mail] da0s1e /usr [homes,databases,htdocs] da1s1b swap da1s1d /usr/obj da1s1e /tmp da2s1d /usr/store [public storage/fileserver] Does anyone know how the system will react to da1 failing? Thanks, Vasek