Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758831AbXJYVqQ (ORCPT ); Thu, 25 Oct 2007 17:46:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752205AbXJYVqB (ORCPT ); Thu, 25 Oct 2007 17:46:01 -0400 Received: from ortiz.unizar.es ([155.210.1.50]:49133 "EHLO ortiz.unizar.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751564AbXJYVqA (ORCPT ); Thu, 25 Oct 2007 17:46:00 -0400 X-Greylist: delayed 2212 seconds by postgrey-1.27 at vger.kernel.org; Thu, 25 Oct 2007 17:46:00 EDT Date: Thu, 25 Oct 2007 23:09:04 +0200 From: "J.A. Magallon" To: "Linux-Kernel, " Subject: Opteron box and 4Gb memory Message-ID: <20071025230904.03d5f46a@werewolf> Organization: GIGA X-Mailer: Claws Mail 3.0.2cvs98 (GTK+ 2.12.0; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Mail-Scanned: Criba 2.0 + Clamd & Bogofilter Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3445 Lines: 75 Hi... I have some Quad-Opteron boxes with 4Gb memory and two of them are running two different Linux distros. Box one sees 4Gb of memory, but box two just sees 3. Their mtrr setups are different: one: [ 0.000000] Linux version 2.6.20... ... [ 0.000000] BIOS-provided physical RAM map: [ 0.000000] BIOS-e820: 0000000000000000 - 000000000009fc00 (usable) [ 0.000000] BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved) [ 0.000000] BIOS-e820: 00000000000e6000 - 0000000000100000 (reserved) [ 0.000000] BIOS-e820: 0000000000100000 - 00000000b7fd0000 (usable) [ 0.000000] BIOS-e820: 00000000b7fd0000 - 00000000b7fde000 (ACPI data) [ 0.000000] BIOS-e820: 00000000b7fde000 - 00000000b8000000 (ACPI NVS) [ 0.000000] BIOS-e820: 00000000fec00000 - 00000000fec01000 (reserved) [ 0.000000] BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved) [ 0.000000] BIOS-e820: 00000000ff780000 - 0000000100000000 (reserved) [ 0.000000] BIOS-e820: 0000000100000000 - 0000000145000000 (usable) [ 0.000000] Entering add_active_range(0, 0, 159) 0 entries of 3200 used [ 0.000000] Entering add_active_range(0, 256, 753616) 1 entries of 3200 used [ 0.000000] Entering add_active_range(0, 1048576, 1331200) 2 entries of 3200 used [ 0.000000] end_pfn_map = 1331200 cat /proc/mtrr: reg00: base=0x00000000 ( 0MB), size=4096MB: write-back, count=1 reg01: base=0x100000000 (4096MB), size=1024MB: write-back, count=1 reg02: base=0x140000000 (5120MB), size= 64MB: write-back, count=1 reg03: base=0x144000000 (5184MB), size= 16MB: write-back, count=1 reg04: base=0xb8000000 (2944MB), size= 128MB: uncachable, count=1 reg05: base=0xc0000000 (3072MB), size=1024MB: uncachable, count=1 two: Linux version 2.6.22.9... ... BIOS-provided physical RAM map: BIOS-e820: 0000000000000000 - 000000000009fc00 (usable) BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved) BIOS-e820: 00000000000e6000 - 0000000000100000 (reserved) BIOS-e820: 0000000000100000 - 00000000b8fd0000 (usable) BIOS-e820: 00000000b8fd0000 - 00000000b8fde000 (ACPI data) BIOS-e820: 00000000b8fde000 - 00000000b9000000 (ACPI NVS) BIOS-e820: 00000000fec00000 - 00000000fec01000 (reserved) BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved) BIOS-e820: 00000000ff780000 - 0000000100000000 (reserved) Entering add_active_range(0, 0, 159) 0 entries of 3200 used Entering add_active_range(0, 256, 757712) 1 entries of 3200 used end_pfn_map = 1048576 cicely:~# cat /proc/mtrr reg00: base=0x00000000 ( 0MB), size=2048MB: write-back, count=1 reg01: base=0x80000000 (2048MB), size= 512MB: write-back, count=1 reg02: base=0xa0000000 (2560MB), size= 256MB: write-back, count=1 reg03: base=0xb0000000 (2816MB), size= 128MB: write-back, count=1 reg04: base=0xb8000000 (2944MB), size= 16MB: write-back, count=1 Why ? Is it a bios setup problem ? A kernel problem ? grep HIGHMEN in configs for both kernels does not give anything, so I still understand less this thing... -- J.A. Magallon \ Software is like sex: \ It's better when it's free MacOS X 10.4.8 Tiger - Darwin Kernel Version 8.8.0 PPC - 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/