From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 29 Dec 2002 23:30:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 29 Dec 2002 23:30:47 -0500 Received: from web13206.mail.yahoo.com ([216.136.174.191]:21351 "HELO web13206.mail.yahoo.com") by vger.kernel.org with SMTP id ; Sun, 29 Dec 2002 23:30:46 -0500 Message-ID: <20021230043908.77703.qmail@web13206.mail.yahoo.com> Date: Sun, 29 Dec 2002 20:39:08 -0800 (PST) From: Anomalous Force Subject: Re: holy grail To: david.lang@digitalinsight.com, jdike@karaya.com Cc: wa@almesberger.net, alan@lxorguk.ukuu.org.uk, riel@conectiva.com.br, ebiederm@xmission.com, linux-kernel@vger.kernel.org In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --- David Lang wrote: > > I think people are at the point of working on this becouse it > sounds like > a worthwhile feature, not becouse it's actually anything that would > be > used. UML sounds like a worthwhile feature, turns out its actually pretty useful too. kexec() is supported in its current incarnation. why not simply extend it the one step further? > > what possible application needs to be able to do a seamless kernel > upgrade > that wouldn't be useing a network? "programs will never use more than 640K of memory." - bill gates lets talk clusters... the teragrid system being built out of 2024 redhat 7.2 installs (ncsa alone, not counting the 3 other cluster sites). imagine a simple system on the network to push a copy of the new kernel and then telling each node to hot-swap. 0 downtime. __super__ easy to maintain. how easy would that become??? how about this... an nfs mount point in the grid for /boot such that each node then gets the kernel from a central point and hot swaps when a flag is set, or a change is detected in the /boot directory. no push even needed then. the cost savings from that alone would be worth the effort to them. > > if it's a batch processing task, it can checkpoint itself and > restart > after a reboot. > 2024 nodes rebooting, how much time needed while the system is in a degraded state? > if it's a controller of specialized equipment then you either can > have the > process checkpoint itself, or you can't afford to pause long enough > to do > the kernel swap (i.e. the device keeps operating regardless and so > may > generate ssignals to the program during the time when you are > swapping > kernels) > hence a queue to catch pending irqs while the system swaps over. ===== Main Entry: anom·a·lous 1 : inconsistent with or deviating from what is usual, normal, or expected: IRREGULAR, UNUSUAL 2 (a) : of uncertain nature or classification (b) : marked by incongruity or contradiction : PARADOXICAL synonym see IRREGULAR __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com