From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964803AbWDCFNW (ORCPT ); Mon, 3 Apr 2006 01:13:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751391AbWDCFNV (ORCPT ); Mon, 3 Apr 2006 01:13:21 -0400 Received: from mail.gmx.net ([213.165.64.20]:40910 "HELO mail.gmx.net") by vger.kernel.org with SMTP id S1751387AbWDCFNV (ORCPT ); Mon, 3 Apr 2006 01:13:21 -0400 X-Authenticated: #14349625 Subject: Re: lowmem_reserve question From: Mike Galbraith To: Con Kolivas Cc: Nick Piggin , ck@vds.kolivas.org, Andrew Morton , linux list In-Reply-To: <200604031448.01391.kernel@kolivas.org> References: <200604021401.13331.kernel@kolivas.org> <200604031248.13532.kernel@kolivas.org> <1144039366.8198.2.camel@homer> <200604031448.01391.kernel@kolivas.org> Content-Type: text/plain Date: Mon, 03 Apr 2006 07:14:07 +0200 Message-Id: <1144041247.8198.8.camel@homer> Mime-Version: 1.0 X-Mailer: Evolution 2.4.0 Content-Transfer-Encoding: 7bit X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2006-04-03 at 14:48 +1000, Con Kolivas wrote: > On Monday 03 April 2006 14:42, Mike Galbraith wrote: > > On Mon, 2006-04-03 at 12:48 +1000, Con Kolivas wrote: > > > Furthermore, now that we have the option of up to 3GB lowmem split on > > > 32bit we can have a default lowmem_reserve of almost 12MB (if I'm reading > > > it right) which seems very tight with only 16MB of ZONE_DMA. > > > > I haven't crawled around in the vm for ages, but I think that's only > > 16MB if you support antique cards. > > That's what the ram is used for, but that is all the ZONE_DMA 32bit machines > get, whether you use it for that purpose or not. My concern is that this will > have all sorts of effects on the balancing since it will always appear almost > full. If that dinky 16MB zone still exists, and always appears nearly full, be happy. It used to be a real PITA. -Mike