From owner-freebsd-current@FreeBSD.ORG Tue Apr 27 11:33:26 2010 Return-Path: Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 8F6FC106566B; Tue, 27 Apr 2010 11:33:26 +0000 (UTC) (envelope-from gavin@FreeBSD.org) Received: from mail-gw2.york.ac.uk (mail-gw2.york.ac.uk [144.32.128.247]) by mx1.freebsd.org (Postfix) with ESMTP id 0282E8FC23; Tue, 27 Apr 2010 11:33:25 +0000 (UTC) Received: from mail-gw7.york.ac.uk (mail-gw7.york.ac.uk [144.32.129.30]) by mail-gw2.york.ac.uk (8.13.6/8.13.6) with ESMTP id o3RBXAee002203; Tue, 27 Apr 2010 12:33:10 +0100 (BST) Received: from buffy-128.york.ac.uk ([144.32.128.160] helo=buffy.york.ac.uk) by mail-gw7.york.ac.uk with esmtps (TLSv1:AES256-SHA:256) (Exim 4.68) (envelope-from ) id 1O6j2M-0005cL-Mq; Tue, 27 Apr 2010 12:33:10 +0100 Received: from buffy.york.ac.uk (localhost [127.0.0.1]) by buffy.york.ac.uk (8.14.3/8.14.3) with ESMTP id o3RBXA3b098505; Tue, 27 Apr 2010 12:33:10 +0100 (BST) (envelope-from gavin@FreeBSD.org) Received: (from ga9@localhost) by buffy.york.ac.uk (8.14.3/8.14.3/Submit) id o3RBXAvH098504; Tue, 27 Apr 2010 12:33:10 +0100 (BST) (envelope-from gavin@FreeBSD.org) X-Authentication-Warning: buffy.york.ac.uk: ga9 set sender to gavin@FreeBSD.org using -f From: Gavin Atkinson To: "M. Warner Losh" In-Reply-To: <20100426.103327.319083499807534535.imp@bsdimp.com> References: <4BD06BD9.6030401@FreeBSD.org> <20100426.103327.319083499807534535.imp@bsdimp.com> Content-Type: text/plain; charset="ASCII" Content-Transfer-Encoding: quoted-printable Date: Tue, 27 Apr 2010 12:33:09 +0100 Message-ID: <1272367989.97887.47.camel@buffy.york.ac.uk> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 FreeBSD GNOME Team Port X-York-MailScanner: Found to be clean X-York-MailScanner-From: gavin@freebsd.org Cc: mav@FreeBSD.org, freebsd-current@FreeBSD.org, freebsd-geom@FreeBSD.org Subject: Re: Switchover to CAM ATA? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 27 Apr 2010 11:33:26 -0000 On Mon, 2010-04-26 at 10:33 -0600, M. Warner Losh wrote: > My opinion for the path forward: > (1) Send a big heads up about the future of ataraid(5). It will be > shot in the head soon, to be replaced be a bunch of geom classes > for each different container format. At least that seems to be > the rough consensus I've seen so far. We need worker bees to do > many of these classes, although much can be mined from the ataraid > code today. Losing ataraid would be bad. I suspect there are a lot of installs using it - especially as there is no way to create any other mirror from sysinstall. However, I'm not actually sure that the functionality it provides is easy to push down into GEOM. ataraid depends on knowing a lot about the underlying hardware, in order to know which format of metadata to use. i.e. it needs to know that the disks are attached to (say) a Highpoint controller. This is especially important when creating new ATA RAID devices, although there is so little identifying metadata on the disks themselves that in some cases it doesn't look like it is possible to identify or even confirm the existence of metadata without knowing the PCI ID of the controller to which the disks are attached. I'm not sure I can see a way to do this from within GEOM. Gavin