Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752468AbZLaCta (ORCPT ); Wed, 30 Dec 2009 21:49:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751735AbZLaCt3 (ORCPT ); Wed, 30 Dec 2009 21:49:29 -0500 Received: from mail.tmr.com ([64.65.253.246]:58918 "EHLO partygirl.tmr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752155AbZLaCt3 (ORCPT ); Wed, 30 Dec 2009 21:49:29 -0500 Message-ID: <4B3C1137.8060308@tmr.com> Date: Wed, 30 Dec 2009 21:49:27 -0500 From: Bill Davidsen User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.21) Gecko/20090507 Fedora/1.1.16-1.fc9 NOT Firefox/3.0.11 pango-text SeaMonkey/1.1.16 MIME-Version: 1.0 To: Linux Kernel mailing List Subject: Re: Ubuntu 32-bit, 32-bit PAE, 64-bit Kernel Benchmarks References: In-Reply-To: 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 Content-Length: 1451 Lines: 28 Yuhong Bao wrote: > Given that Linus was once talking about the performance penalties of PAE and HIGHMEM64G, perhaps you'd find these benchmarks done by Phoronix of interest: > http://www.phoronix.com/scan.php?page=article&item=ubuntu_32_pae > I find these tests mirror my own experience with PAE, the benefit of having the nx hardware enabled justifies the few percent drop in performance I was able to find. I find the huge gain in web service hard to believe without a hint why a 64 bit CPU would be 15x faster. The disk, memory, and network wouldn't be faster, and the CPU intensive tests weren't significantly faster, so unless the systems were tuned differently where's the gain? Same feeling about the TP test, an order of magnitude faster on a test running the same application on the same hardware is hard to buy without an explanation. The only obvious source I can think of is running the test load at 100Mbit on one test and Gbit on another, because I saw an early network driver do just that in negotiations with a switch. -- Bill Davidsen "We have more to fear from the bungling of the incompetent than from the machinations of the wicked." - from Slashdot -- 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/