From owner-cvs-src@FreeBSD.ORG Wed Feb 21 18:31:46 2007 Return-Path: X-Original-To: cvs-src@freebsd.org Delivered-To: cvs-src@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 98C0A16F80F; Wed, 21 Feb 2007 18:31:46 +0000 (UTC) (envelope-from kris@obsecurity.org) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.freebsd.org (Postfix) with ESMTP id 8615013C481; Wed, 21 Feb 2007 18:31:46 +0000 (UTC) (envelope-from kris@obsecurity.org) Received: from obsecurity.dyndns.org (elvis.mu.org [192.203.228.196]) by elvis.mu.org (Postfix) with ESMTP id 65D911A4D83; Wed, 21 Feb 2007 10:31:46 -0800 (PST) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id 2F7F953E03; Wed, 21 Feb 2007 13:31:45 -0500 (EST) Date: Wed, 21 Feb 2007 13:31:45 -0500 From: Kris Kennaway To: Robert Watson Message-ID: <20070221183144.GA14052@xor.obsecurity.org> References: <200702202204.l1KM4NV4037929@repoman.freebsd.org> <20070221103350.P80197@fledge.watson.org> <200702210607.08422.jhb@freebsd.org> <20070221111242.X80197@fledge.watson.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070221111242.X80197@fledge.watson.org> User-Agent: Mutt/1.4.2.2i Cc: cvs-src@freebsd.org, cvs-all@freebsd.org, src-committers@freebsd.org, Nick Hibma , John Baldwin Subject: Re: cvs commit: src/sbin/mdconfig mdconfig.8 mdconfig.c X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Feb 2007 18:31:46 -0000 On Wed, Feb 21, 2007 at 11:13:09AM +0000, Robert Watson wrote: > > On Wed, 21 Feb 2007, John Baldwin wrote: > > >On Wednesday 21 February 2007 05:36, Robert Watson wrote: > >> > >>On Tue, 20 Feb 2007, Nick Hibma wrote: > >> > >>>n_hibma 2007-02-20 22:04:23 UTC > >>> > >>> FreeBSD src repository > >>> > >>> Modified files: > >>> sbin/mdconfig mdconfig.8 mdconfig.c > >>> Log: > >>> Kris suggested that swap is a better choice as a default than malloc. > >>> > >>> MFC: 1 week > >> > >>Are you sure this should be MFC'd? While I agree with the change in > >>principle, it will cause systems currently using malloc-backed md devices > >>to mysteriously switch to swap-backed. How will this behave on systems > >>that don't have swap, such as pure diskless systems not using NFS-backed > >>swap? This isn't a strong objection per se, but it could be that rc.d > >>scripts need tweaking for diskless environments if they currently do use > >>malloc-back md devices based on that being the default. > > > >I don't think this changes the default for anything in 6.x. He changed > >the default for his patch from yesterday that made it assume a type if you > >do 'mdconfig -s '. Currently you have to do: > > > >'mdconfig -a -t malloc -s ' or 'mdconfig -a -t swap -s ' > > > >but Nick changed it so just '-s ' implied '-a -t malloc', and now > >he's changed it to imply '-a -t swap'. > > Ah, OK. This sounds reasonable. Anyway, swap-backing can't really have a worse failure mode than malloc backing in the event that backing store becomes unavailable (e.g. no swap is configured and ram is full): malloc will already panic in that situation. Kris