From owner-freebsd-stable@FreeBSD.ORG Sat May 24 16:53:30 2008 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3D1FB106568F for ; Sat, 24 May 2008 16:53:30 +0000 (UTC) (envelope-from andrew@thefrog.net) Received: from fk-out-0910.google.com (fk-out-0910.google.com [209.85.128.186]) by mx1.freebsd.org (Postfix) with ESMTP id 64A198FC0A for ; Sat, 24 May 2008 16:53:29 +0000 (UTC) (envelope-from andrew@thefrog.net) Received: by fk-out-0910.google.com with SMTP id k31so1195683fkk.11 for ; Sat, 24 May 2008 09:53:28 -0700 (PDT) Received: by 10.82.167.9 with SMTP id p9mr16877bue.40.1211646397176; Sat, 24 May 2008 09:26:37 -0700 (PDT) Received: by 10.82.149.3 with HTTP; Sat, 24 May 2008 09:26:37 -0700 (PDT) Message-ID: <16a6ef710805240926t3b4f631bja349fed8df6785ff@mail.gmail.com> Date: Sun, 25 May 2008 02:26:37 +1000 From: "Andrew Hill" Sender: andrew@thefrog.net To: "Arnaud Houdelette" MIME-Version: 1.0 X-Google-Sender-Auth: 1651b4643b5f72be Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-stable@freebsd.org Subject: ZFS on root and disk write caching. X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 24 May 2008 16:53:30 -0000 I don't have a definite answer to your first two questions (I've got a similar set up and would be interested to get some definite answers to those) however I'd like to comment on your third point... On May 21, 11:00 pm, arnaud.houdele...@tzim.net (Arnaud Houdelette) wrote: > 3. I'd like to keep the storage pool (zraid1) separated from the system > pool (just one disk). The wiki states that we may encounter problems > with more than one pool in use : is it still the case ? as for encountering problems with multiple zpools, my impression from the mailing lists is that it seems to work fine for some people and not for others... (i'm in the latter category, unfortunately) but what struck me as odd is the desire to create two separate zpools - one for data storage and one for the system. i think one of zfs's greatest strengths is the abstraction/separation between disks and filesystems. unless you're planning on removing/recreating the raidz1 pool in the near future, it seems a bit odd to put your system on a single/separate, non-redundant drive when you could just create a raidz across all four disks with storage and system filesystems in the one raidz pool. this way you don't lose anything if the disk you chose to run the OS from happens to fail, or even just gets a bad sector in an unfortunately crucial location... And even if you were going to recreate the raidz pool in the near future, it shouldn't be too hard to backup the system filesystems with zfs snapshot/send/receive commands, recreate the pool and then restore the system filesystems from the backup Andrew