Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262003AbTIPRPt (ORCPT ); Tue, 16 Sep 2003 13:15:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262004AbTIPRO3 (ORCPT ); Tue, 16 Sep 2003 13:14:29 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.31.123]:41189 "EHLO atrey.karlin.mff.cuni.cz") by vger.kernel.org with ESMTP id S262000AbTIPROR (ORCPT ); Tue, 16 Sep 2003 13:14:17 -0400 Date: Tue, 16 Sep 2003 19:10:57 +0200 From: Pavel Machek To: Alan Cox Cc: Stephan von Krawczynski , Marcelo Tosatti , neilb@cse.unsw.edu.au, Linux Kernel Mailing List Subject: Re: experiences beyond 4 GB RAM with 2.4.22 Message-ID: <20030916171057.GA8210@openzaurus.ucw.cz> References: <20030916102113.0f00d7e9.skraw@ithnet.com> <20030916153658.3081af6c.skraw@ithnet.com> <1063722973.10037.65.camel@dhcp23.swansea.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1063722973.10037.65.camel@dhcp23.swansea.linux.org.uk> User-Agent: Mutt/1.3.27i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1249 Lines: 27 Hi! > > Well, I do understand the bounce buffer problem, but honestly the current way > > of handling the situation seems questionable at least. If you ever tried such a > > system you notice it is a lot worse than just dumping the additional ram above > > 4GB. You can really watch your network connections go bogus which is just > > unacceptable. Is there any thinkable way to ommit the bounce buffers and still > > do something useful with the beyond-4GB ram parts? > > The 2.6 tree is somewhat better about this but at the end of the day if > your I/O subsystem can't do the job your box will not perform ideally. > For some workloads its a huge win to have the extra RAM, for others the > I/O is a real pain. If he has trouble logging in, then there's a bug somewhere. Bounce buffers should not slow machine down more than 2x, and from his description it looks like way worse slowdown. Pavel -- Pavel Written on sharp zaurus, because my Velo1 broke. If you have Velo you don't need... - 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/