From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1N2196-0003xD-2E for mharc-grub-devel@gnu.org; Sun, 25 Oct 2009 07:20:24 -0400 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1N2193-0003vS-LM for grub-devel@gnu.org; Sun, 25 Oct 2009 07:20:21 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1N218y-0003u5-85 for grub-devel@gnu.org; Sun, 25 Oct 2009 07:20:20 -0400 Received: from [199.232.76.173] (port=38101 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1N218y-0003u2-2d for grub-devel@gnu.org; Sun, 25 Oct 2009 07:20:16 -0400 Received: from smarthost02.mail.zen.net.uk ([212.23.3.141]:47673) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1N218x-0000Xl-PV for grub-devel@gnu.org; Sun, 25 Oct 2009 07:20:15 -0400 Received: from [82.69.40.219] (helo=riva.pelham.vpn.ucam.org) by smarthost02.mail.zen.net.uk with esmtp (Exim 4.63) (envelope-from ) id 1N218w-000082-Ux for grub-devel@gnu.org; Sun, 25 Oct 2009 11:20:15 +0000 Received: from cjwatson by riva.pelham.vpn.ucam.org with local (Exim 3.36 #1 (Debian)) for grub-devel@gnu.org id 1N218p-0005Q1-00; Sun, 25 Oct 2009 11:20:07 +0000 Date: Sun, 25 Oct 2009 11:20:07 +0000 From: Colin Watson To: The development of GRUB 2 Message-ID: <20091025112007.GI28534@riva.ucam.org> References: <20091025003617.GH28534@riva.ucam.org> <4AE41A15.7050504@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4AE41A15.7050504@gmail.com> User-Agent: Mutt/1.5.18 (2008-05-17) X-Originating-Smarthost02-IP: [82.69.40.219] X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6 (newer, 3) Subject: Re: [PATCH] Support RAID on virtio devices, and others X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: The development of GRUB 2 List-Id: The development of GRUB 2 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 25 Oct 2009 11:20:21 -0000 On Sun, Oct 25, 2009 at 10:27:49AM +0100, Vladimir 'phcoder' Serbinenko wrote: > Colin Watson wrote: > > GRUB only supports RAID on a relatively small number of device types, as > > implemented by grub_util_getdiskname. I received a bug report noting > > that this doesn't work for RAID arrays with virtio block devices (often > > used in kvm) as components. This is difficult to support using the > > approach taken by grub_util_getdiskname, as virtio devices use dynamic > > major numbers. > > > > find_root_device in util/getroot.c seemed to be exactly what I wanted: > > it just trawls /dev for the appropriate major and minor numbers. This > > code is not performance-critical, so that should be fine. > > Not true. Even in current state grub-mkconfig is taking considerable > time to complete on my system with numerous kernels. Unless someone > implements a cache (it can be invalidated after 5 minutes) not to go > through the same probing procedure on every grub-probe call I object > against adding any additional delay in probing procedure But this code is not called from grub-probe; it is only called from grub-setup (grep for grub_util_raid_getmembers to confirm for yourself). A grub-mkconfig run shouldn't go anywhere near this. -- Colin Watson [cjwatson@ubuntu.com]