From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763322AbZDII4o (ORCPT ); Thu, 9 Apr 2009 04:56:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761160AbZDIIzE (ORCPT ); Thu, 9 Apr 2009 04:55:04 -0400 Received: from mx.narancs.net ([85.186.77.202]:46723 "EHLO ds9.narancs.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762717AbZDIIy7 (ORCPT ); Thu, 9 Apr 2009 04:54:59 -0400 X-Greylist: delayed 469 seconds by postgrey-1.27 at vger.kernel.org; Thu, 09 Apr 2009 04:54:59 EDT Message-ID: <49DDB609.8050405@narancs.net> Date: Thu, 09 Apr 2009 11:47:05 +0300 From: Imre Gergely User-Agent: Thunderbird 2.0.0.21 (X11/20090318) MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: Finding lost memory + kernel messages explained X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi I've just upgraded my laptop RAM from 1x2GB to 2x2GB. The BIOS says 4096MB, memtest says 4031MB (I'm not sure why, but let's assume it's right). After Linux boots, Ubuntu 8.10 x86_64, with Linux gimre-laptop 2.6.27-11-generic #1 SMP Wed Apr 1 20:53:41 UTC 2009 x86_64 GNU/Linux I look at /proc/meminfo, and I don't have 4031MB: gimre@gimre-laptop:~$ cat /proc/meminfo MemTotal: 3989844 kB MemFree: 3157756 kB That would be around 3896MB. My question is: where does the memory go? Is it normal to 'lose' that much (~130MB) ? Here's the dmesg output http://pastebin.com/m4f7d089a Also I would like to know more about those kernel messages, what do all those numbers, and memory mappings and all that mean? Is there a comprehensive manual / howto / wiki which explains all the messages in more detail? One thing I tried was appending iommu=off at boot, which gave me back some 50MB, but there were still 80MB missing and the USB mouse didn't work (among other things I'm sure). Laptop is a HP Compaq 8510p. Thanks. -- Imre Gergely Yahoo!: gergelyimre ICQ#: 101510959 MSN: gergely_imre GoogleTalk: gergelyimre gpg --keyserver subkeys.pgp.net --recv-keys 0x34525305