Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758740Ab0APCGS (ORCPT ); Fri, 15 Jan 2010 21:06:18 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758717Ab0APCGR (ORCPT ); Fri, 15 Jan 2010 21:06:17 -0500 Received: from snt0-omc2-s24.snt0.hotmail.com ([65.55.90.99]:33479 "EHLO snt0-omc2-s24.snt0.hotmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758696Ab0APCGR convert rfc822-to-8bit (ORCPT ); Fri, 15 Jan 2010 21:06:17 -0500 Message-ID: X-Originating-IP: [96.253.143.208] From: Yuhong Bao To: CC: Linus Torvalds , , Subject: RE: Ubuntu 32-bit, 32-bit PAE, 64-bit Kernel Benchmarks Date: Fri, 15 Jan 2010 18:06:13 -0800 Importance: Normal In-Reply-To: <4B511B12.6010208@zytor.com> References: ,<4B511B12.6010208@zytor.com> Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 X-OriginalArrivalTime: 16 Jan 2010 02:06:13.0659 (UTC) FILETIME=[7AE0E6B0:01CA9650] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > The big difference isn't between HIGHMEM4G (no PAE) and HIGHMEM64G > (PAE), it's between HIGHMEM and !HIGHMEM. That cutoff is ~892 MB for a > stock 32-bit kernel. Unfortunately most desktop/laptop systems nowadays ship with more than 1GB.Luckily, in the case of Atom netbooks that Linus mentioned, most Atom netbooks ship with only 1GB of RAM, partly due to MS's restrictions.However, disabling HIGHMEM will turn off NX which all Atom CPUs have, unless you turn CONFIG_PAE back on. Yuhong Bao _________________________________________________________________ Hotmail: Trusted email with Microsoft?s powerful SPAM protection. http://clk.atdmt.com/GBL/go/196390706/direct/01/-- 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/