Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265828AbUFXWRx (ORCPT ); Thu, 24 Jun 2004 18:17:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265768AbUFXWQb (ORCPT ); Thu, 24 Jun 2004 18:16:31 -0400 Received: from fw.osdl.org ([65.172.181.6]:9347 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S265837AbUFXWJB (ORCPT ); Thu, 24 Jun 2004 18:09:01 -0400 Date: Thu, 24 Jun 2004 15:11:30 -0700 From: Andrew Morton To: wli@holomorphy.com, andrea@suse.de, nickpiggin@yahoo.com.au, tiwai@suse.de, ak@suse.de, ak@muc.de, tripperda@nvidia.com, discuss@x86-64.org, linux-kernel@vger.kernel.org Subject: Re: [discuss] Re: 32-bit dma allocations on 64-bit platforms Message-Id: <20040624151130.4a444973.akpm@osdl.org> In-Reply-To: <20040624145441.181425c8.akpm@osdl.org> References: <20040623213643.GB32456@hygelac> <20040623234644.GC38425@colin2.muc.de> <20040624112900.GE16727@wotan.suse.de> <20040624164258.1a1beea3.ak@suse.de> <20040624152946.GK30687@dualathlon.random> <40DAF7DF.9020501@yahoo.com.au> <20040624165200.GM30687@dualathlon.random> <20040624165629.GG21066@holomorphy.com> <20040624145441.181425c8.akpm@osdl.org> X-Mailer: Sylpheed version 0.9.7 (GTK+ 1.2.10; i586-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1608 Lines: 41 Andrew Morton wrote: > > Note that this code was sigificantly changed between 2.6.5 and 2.6.7. Here's the default setup on a 1G ia32 box: DMA free:4172kB min:16kB low:32kB high:48kB active:0kB inactive:0kB present:16384kB protections[]: 8 476 540 Normal free:54632kB min:936kB low:1872kB high:2808kB active:278764kB inactive:253668kB present:901120kB protections[]: 0 468 532 HighMem free:308kB min:128kB low:256kB high:384kB active:87972kB inactive:40300kB present:130516kB protections[]: 0 0 64 ie: - protect 8 pages from ZONE_DMA from a GFP_DMA allocation attempt - protect 476 pages from ZONE_DMA from a GFP_KERNEL allocation attempt - protect 540 pages from ZONE_DMA from a GFP_HIGHMEM allocation attempt. etcetera. After setting lower_zone_protection to 10: Active:111515 inactive:65009 dirty:116 writeback:0 unstable:0 free:3290 slab:75489 mapped:52247 pagetables:446 DMA free:4172kB min:16kB low:32kB high:48kB active:0kB inactive:0kB present:16384kB protections[]: 8 5156 5860 Normal free:8736kB min:936kB low:1872kB high:2808kB active:352780kB inactive:224972kB present:901120kB protections[]: 0 468 1172 HighMem free:252kB min:128kB low:256kB high:384kB active:93280kB inactive:35064kB present:130516kB protections[]: 0 0 64 It's a bit complex, and perhaps the relative levels of the various thresholds could be tightened up. - 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/