From owner-svn-src-head@freebsd.org Wed Aug 17 17:57:37 2016 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 23085BBD7D2; Wed, 17 Aug 2016 17:57:37 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from citapm.icyb.net.ua (citapm.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id D6C361604; Wed, 17 Aug 2016 17:57:35 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from porto.starpoint.kiev.ua (porto-e.starpoint.kiev.ua [212.40.38.100]) by citapm.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id UAA10915; Wed, 17 Aug 2016 20:57:28 +0300 (EEST) (envelope-from avg@FreeBSD.org) Received: from localhost ([127.0.0.1]) by porto.starpoint.kiev.ua with esmtp (Exim 4.34 (FreeBSD)) id 1ba55j-000ID5-UU; Wed, 17 Aug 2016 20:57:27 +0300 Subject: Re: svn commit: r304142 - head/usr.sbin/bsdinstall/partedit To: Nathan Whitehorn , Warner Losh References: <201608150930.u7F9UL1V069576@repo.freebsd.org> <861t1n6749.fsf@desk.des.no> <581c856c-826b-529e-c9c6-a397fb679708@freebsd.org> <86wpjf4eun.fsf@desk.des.no> <8cb3fa1a-50cb-e238-d006-b98a628d446d@freebsd.org> <445700cb-c4b4-9272-df17-a851a6200543@freebsd.org> Cc: =?UTF-8?Q?Dag-Erling_Sm=c3=b8rgrav?= , src-committers , "svn-src-all@freebsd.org" , "svn-src-head@freebsd.org" From: Andriy Gapon Message-ID: Date: Wed, 17 Aug 2016 20:56:31 +0300 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <445700cb-c4b4-9272-df17-a851a6200543@freebsd.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 17 Aug 2016 17:57:37 -0000 On 17/08/2016 19:36, Nathan Whitehorn wrote: > OK, so then what is the solution here? We have a number of tools that need to > know this information: gpart, sade, bsdinstall, zfs, graid, etc. If we want to > have a consistent set of defaults -- for example, to use 4K across the board, > which I think is a good idea -- there should be a central place to set this that > does not involve hacking a variety of independent tools. Do you disagree? > > I don't care how that happens. It happens that the way we currently encode this > is geom stripesize. If we feel like we can't get this right in drivers, then we > should provide a tunable to set a minimum default alignment. You could implement > this in lots of different ways. But having static values hardcoded in random > places that makes similar tools (sade, gpart) behave inconsistently cannot > possibly be the answer. > > This is my point, from beginning to end. Is there any reason -- at all -- that > we should prefer per-tool one-off changes to fixing the central mechanism we > already have to give consistent results that we think are reliable? It would be perfect to get a correct description of a disk and to do that in central place. But still I, as a user / administrator, want to be able to _force_ the alignment that I want when I partition a disk, create a filesystem, etc. That is, even if the kernel reports the perfectly correct information and the tools know how to automatically do what's best for me, I still want to eb able to override. And I think that installers and administrative tools should provide a way to do that. And many already do, e.g. 'gpart add -a X'. So, I do not see how striving for the better disk detection (in a central place) and having more knobs in the administration tools are mutually exclusive or conflicting goals. Just my two bits. -- Andriy Gapon