Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751077AbVJXPNi (ORCPT ); Mon, 24 Oct 2005 11:13:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751081AbVJXPNi (ORCPT ); Mon, 24 Oct 2005 11:13:38 -0400 Received: from clock-tower.bc.nu ([81.2.110.250]:7816 "EHLO lxorguk.ukuu.org.uk") by vger.kernel.org with ESMTP id S1751077AbVJXPNh (ORCPT ); Mon, 24 Oct 2005 11:13:37 -0400 Subject: Re: ioctls, etc. (was Re: [PATCH 1/4] sas: add flag for locally attached PHYs) From: Alan Cox To: Luben Tuikov Cc: Christoph Hellwig , Sergey Panov , Stefan Richter , linux-scsi@vger.kernel.org, Linux Kernel , Jeff Garzik , andrew.patterson@hp.com, Christoph Hellwig , "Moore, Eric Dean" , jejb@steeleye.com, Linus Torvalds In-Reply-To: <435CE6CA.4070704@adaptec.com> References: <4359440E.2050702@pobox.com> <43595275.1000308@adaptec.com> <435959BE.5040101@pobox.com> <43595CA6.9010802@adaptec.com> <43596070.3090902@pobox.com> <43596859.3020801@adaptec.com> <43596F16.7000606@pobox.com> <435A1793.1050805@s5r6.in-berlin.de> <20051022105815.GB3027@infradead.org> <1129994910.6286.21.camel@sipan.sipan.org> <20051022171943.GA7546@infradead.org> <435CE6CA.4070704@adaptec.com> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Mon, 24 Oct 2005 16:41:35 +0100 Message-Id: <1130168495.12873.27.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1063 Lines: 22 On Llu, 2005-10-24 at 09:51 -0400, Luben Tuikov wrote: > controls and how. Understanding how the factory workers use it and what > they expect. Understanding the code (which may not be as easy). Then it > is rewritten so that it can be easily supported and maintained. Very very rarely, because it means down time and supporting two systems at once. Take a look at the australian customs fiasco or the british passport office disaster to see why (actually almost any large government IT project where politics dictated 'write new stuff so I can announce it in parliament'). The smart factory update would occur piece by piece. Starting with the most pressing problems (ie fastest ROI) and working to a plan that ends up with the system modular and clean. You don't turn a steel plant off for a software upgrade. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/