Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262997AbTIRHJL (ORCPT ); Thu, 18 Sep 2003 03:09:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262998AbTIRHJL (ORCPT ); Thu, 18 Sep 2003 03:09:11 -0400 Received: from ns.virtualhost.dk ([195.184.98.160]:44441 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id S262997AbTIRHJI (ORCPT ); Thu, 18 Sep 2003 03:09:08 -0400 Date: Thu, 18 Sep 2003 09:08:45 +0200 From: Jens Axboe To: Marcelo Tosatti Cc: Alan Cox , Olivier Galibert , Stephan von Krawczynski , neilb@cse.unsw.edu.au, Linux Kernel Mailing List Subject: Re: experiences beyond 4 GB RAM with 2.4.22 Message-ID: <20030918070845.GS906@suse.de> References: <20030917191946.GQ906@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1513 Lines: 41 On Wed, Sep 17 2003, Marcelo Tosatti wrote: > > > On Wed, 17 Sep 2003, Jens Axboe wrote: > > > On Wed, Sep 17 2003, Alan Cox wrote: > > > On Maw, 2003-09-16 at 20:58, Olivier Galibert wrote: > > > > On Tue, Sep 16, 2003 at 04:29:02PM +0100, Alan Cox wrote: > > > > > The kernel has no idea what you will do with given ram. It does try to > > > > > make some guesses but you are basically trying to paper over hardware > > > > > limits. > > > > > > > > Is there a way to specifically turn that ram into a tmpfs though? > > > > > > > > > Something like z2ram copied and hacked a little to kmap the blocks it > > > wants would give you a block device you could use for swap or for /tmp. > > > Im not sure tmpfs would work here > > > > Aditionally, you need GFP_DMA32 or similar. Would also alleviate the > > nasty pressure on ZONE_NORMAL which is often quite stressed. > > IMO such GFP_DMA32 flag is a bit intrusive for 2.4, isnt it? Not really, it's just an extra zone. Maybe I can dig such a patch up, I had one for 2.4.2-pre something... > What has been done in 2.6 in respect to the excessive normal zone > pressure and bounce buffering problems? Nothing, afaic. 2.6 isn't even completely deadlock free when it comes to bounce buffering. -- Jens Axboe - 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/