From owner-freebsd-fs@FreeBSD.ORG Wed Dec 21 07:22:07 2011 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 60128106566B for ; Wed, 21 Dec 2011 07:22:07 +0000 (UTC) (envelope-from ndenev@gmail.com) Received: from mail-ee0-f54.google.com (mail-ee0-f54.google.com [74.125.83.54]) by mx1.freebsd.org (Postfix) with ESMTP id E7B338FC13 for ; Wed, 21 Dec 2011 07:22:06 +0000 (UTC) Received: by eekc50 with SMTP id c50so8588229eek.13 for ; Tue, 20 Dec 2011 23:22:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=subject:mime-version:content-type:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to:x-mailer; bh=6ynAqBbEPQ3iIUCGKIVxG00HOHr916Rj2fhYgDnLov8=; b=IhLYzfHqEOALI+XCpoExismIcAAAw8l3gPK+0XZy6sJ8chunndXxqhGvlA9A4ujNUm +7n6lYHDroTkPVdn+gYSB43xyfyc6xBdJV533cttV/sDBlP5BqPQh3X6IpWWW11gNNYu YLr6jlUl5z0aqCosBFMWnR209IQaIWaVFpBos= Received: by 10.14.4.229 with SMTP id 77mr760839eej.7.1324450408215; Tue, 20 Dec 2011 22:53:28 -0800 (PST) Received: from imba-brutale.totalterror.net ([93.152.152.135]) by mx.google.com with ESMTPS id q28sm17076455eea.6.2011.12.20.22.53.25 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 20 Dec 2011 22:53:26 -0800 (PST) Mime-Version: 1.0 (Apple Message framework v1251.1) Content-Type: text/plain; charset=iso-8859-1 From: Nikolay Denev In-Reply-To: <4EEF321E.5090806@barafranca.com> Date: Wed, 21 Dec 2011 08:53:24 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: <654420CC-9E7D-4BAA-AC14-4F49196DFC74@gmail.com> References: <4EEF321E.5090806@barafranca.com> To: Hugo Silva X-Mailer: Apple Mail (2.1251.1) Cc: freebsd-fs@FreeBSD.ORG Subject: Re: ZFS: root pool considerations, multiple pools on the same disk X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Dec 2011 07:22:07 -0000 On Dec 19, 2011, at 2:46 PM, Hugo Silva wrote: > Hello, >=20 > I've been doing some tests with 9.0 RC3 and ZFS. This particular = server > has 6 disks and a single zpool on mfid?p3 partitions, which I've > temporarily arranged into a raid-10 with 2 spares, single pool. >=20 >=20 > I've been thinking about whether it makes sense to separate the rpool > from the data pool(s).. >=20 > It seems to make sense at some levels to separate the rpool from the > app/user data, but to me it's less clear whether this is a good idea = or > not when the backing disks are all the same. >=20 > One idea would be creating a 4-way mirror on small partitions for the > rpool (sturdier), and a zfs raid-10 on the remaining larger partition. >=20 > I'm curious about the performance implications (if any) of having >1 > zpools on the same disks (considering that during normal usage, it'll = be > the data pool seeing 99.999% of the action) and whether anyone has > thought the same and/or applied this concept in production. >=20 > Regards, >=20 > Hugo Hello, It depends on what you will run on the machine but keep in mind that the root pool is limited to a single vdev and you cannot add ZIL/LOG = devices to=20 the root pool. As for the performance, I don't think it will make a difference having = separate root and data pools, except that you will have less spindles for the data pool. Regards, Nikolay=