Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751877AbWHUN1z (ORCPT ); Mon, 21 Aug 2006 09:27:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751872AbWHUN1z (ORCPT ); Mon, 21 Aug 2006 09:27:55 -0400 Received: from roadrunner-base.egenera.com ([63.160.166.46]:4234 "EHLO roadrunner-base.egenera.com") by vger.kernel.org with ESMTP id S1751875AbWHUN1y (ORCPT ); Mon, 21 Aug 2006 09:27:54 -0400 Date: Mon, 21 Aug 2006 09:27:17 -0400 From: "Philip R. Auld" To: Andrew Morton Cc: Daniel Phillips , Peter Zijlstra , David Miller , riel@redhat.com, tgraf@suug.ch, linux-mm@kvack.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Mike Christie Subject: Re: [RFC][PATCH 2/9] deadlock prevention core Message-ID: <20060821132717.GD26589@vienna.egenera.com> References: <1155530453.5696.98.camel@twins> <20060813215853.0ed0e973.akpm@osdl.org> <44E3E964.8010602@google.com> <20060816225726.3622cab1.akpm@osdl.org> <44E5015D.80606@google.com> <20060817230556.7d16498e.akpm@osdl.org> <44E62F7F.7010901@google.com> <20060818153455.2a3f2bcb.akpm@osdl.org> <44E650C1.80608@google.com> <20060818194435.25bacee0.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060818194435.25bacee0.akpm@osdl.org> User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1749 Lines: 47 Hi Andrew, Rumor has it that on Fri, Aug 18, 2006 at 07:44:35PM -0700 Andrew Morton said: > On Fri, 18 Aug 2006 16:44:01 -0700 > Daniel Phillips wrote: > > - We expect that the lots-of-dirty-anon-memory-over-swap-over-network > scenario might still cause deadlocks. > > I assert that this can be solved by putting swap on local disks. Peter > asserts that this isn't acceptable due to disk unreliability. I point > out that local disk reliability can be increased via MD, all goes quiet. Putting swap on local disks really messes up the concept of stateless servers. I suppose you can do some sort of swap encryption, but otherwise you need to scrub the swap partition on boot if you re-purpose the hardware. You also then need to do hardware configuration to make sure the local disks are all setup the same way across all server platforms so the common images can boot. Please don't require a hardware solution to a software problem. > > A good exposition which helps us to understand whether and why a > significant proportion of the target user base still wishes to do > swap-over-network would be useful. > I can't claim to represent a significant proportion of the target user base. However, stateless hardware is a powerful and useful model. Cheers, Phil -- Philip R. Auld, Ph.D. Egenera, Inc. Software Architect 165 Forest St. (508) 858-2628 Marlboro, MA 01752 - 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/