From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755652AbZGMMTO (ORCPT ); Mon, 13 Jul 2009 08:19:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755617AbZGMMTN (ORCPT ); Mon, 13 Jul 2009 08:19:13 -0400 Received: from one.firstfloor.org ([213.235.205.2]:49623 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755562AbZGMMTN (ORCPT ); Mon, 13 Jul 2009 08:19:13 -0400 Date: Mon, 13 Jul 2009 14:19:11 +0200 From: Andi Kleen To: linux-kernel@vger.kernel.org, akpm@osdl.org Cc: rdunlap@xenotime.net, linux-doc@vger.kernel.org Subject: [PATCH] Remove some very outdated recommendations in Documentation/memory.txt Message-ID: <20090713121911.GA31442@basil.fritz.box> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Remove some very outdated recommendations in Documentation/memory.txt Signed-off-by: Andi Kleen --- Documentation/memory.txt | 31 ++----------------------------- 1 file changed, 2 insertions(+), 29 deletions(-) Index: linux-2.6.31-rc1-ak/Documentation/memory.txt =================================================================== --- linux-2.6.31-rc1-ak.orig/Documentation/memory.txt +++ linux-2.6.31-rc1-ak/Documentation/memory.txt @@ -1,18 +1,7 @@ There are several classic problems related to memory on Linux systems. - 1) There are some buggy motherboards which cannot properly - deal with the memory above 16MB. Consider exchanging - your motherboard. - - 2) You cannot do DMA on the ISA bus to addresses above - 16M. Most device drivers under Linux allow the use - of bounce buffers which work around this problem. Drivers - that don't use bounce buffers will be unstable with - more than 16M installed. Drivers that use bounce buffers - will be OK, but may have slightly higher overhead. - - 3) There are some motherboards that will not cache above + 1) There are some motherboards that will not cache above a certain quantity of memory. If you have one of these motherboards, your system will be SLOWER, not faster as you add more memory. Consider exchanging your @@ -24,7 +13,7 @@ It can also tell Linux to use less memor If you use "mem=" on a machine with PCI, consider using "memmap=" to avoid physical address space collisions. -See the documentation of your boot loader (LILO, loadlin, etc.) about +See the documentation of your boot loader (LILO, grub, loadlin, etc.) about how to pass options to the kernel. There are other memory problems which Linux cannot deal with. Random @@ -42,19 +31,3 @@ Try: with the vendor. Consider testing it with memtest86 yourself. * Exchanging your CPU, cache, or motherboard for one that works. - - * Disabling the cache from the BIOS. - - * Try passing the "mem=4M" option to the kernel to limit - Linux to using a very small amount of memory. Use "memmap="-option - together with "mem=" on systems with PCI to avoid physical address - space collisions. - - -Other tricks: - - * Try passing the "no-387" option to the kernel to ignore - a buggy FPU. - - * Try passing the "no-hlt" option to disable the potentially - buggy HLT instruction in your CPU.