Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751850AbWIRRWz (ORCPT ); Mon, 18 Sep 2006 13:22:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751852AbWIRRWz (ORCPT ); Mon, 18 Sep 2006 13:22:55 -0400 Received: from ns2.suse.de ([195.135.220.15]:3000 "EHLO mx2.suse.de") by vger.kernel.org with ESMTP id S1751850AbWIRRWz (ORCPT ); Mon, 18 Sep 2006 13:22:55 -0400 To: Helge Hafting Cc: linux-kernel , yogyas@gmail.com Subject: Re: How much kernel memory is in 64-bit OS ? References: <450EA198.5060302@aitel.hist.no> From: Andi Kleen Date: 18 Sep 2006 19:22:52 +0200 In-Reply-To: <450EA198.5060302@aitel.hist.no> Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 902 Lines: 22 Helge Hafting writes: > The requirement for using a 4G/4G split is to have a processor > that support 64-bit adressing as well as 32-bit backward compatibility. s/64/36/. But it's actually not true: 4/4 works on 32bit phys non PAE system too (iirc Fedora forced it for some time even on unsuspecting P-M/VIA C3/586 users who only do 32bit). > > 2) how it is managed ? > The kernel runs in 64-bit mode, offering the 4G/4G stuff for 32-bit > processes. No. > > > 3) how HIGH_MEMORY concept is related here. > high memory is a quirky way of supporting more than 4G on a 32-bit More than ~900MB with a default split. -Andi - 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/