From owner-freebsd-stable@FreeBSD.ORG Mon Apr 12 23:24:41 2010 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 91C37106566B for ; Mon, 12 Apr 2010 23:24:41 +0000 (UTC) (envelope-from maho.nakata@gmail.com) Received: from mail-gy0-f182.google.com (mail-gy0-f182.google.com [209.85.160.182]) by mx1.freebsd.org (Postfix) with ESMTP id 3C4A48FC0A for ; Mon, 12 Apr 2010 23:24:40 +0000 (UTC) Received: by gyh20 with SMTP id 20so3431846gyh.13 for ; Mon, 12 Apr 2010 16:24:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:sender:date:message-id:to:cc :subject:from:in-reply-to:references:x-mailer:mime-version :content-type:content-transfer-encoding; bh=tacrzA8n9csGz7I5LkMEiidyQaAWI0w3pw/PjreQ0D4=; b=Fb12nx5Ce6zC4bxe/245FflZW2+3wnryxVEnB7zFZfxEL5LjwQxhcsKni2UG8+EDXV Tf7V3xsb80T5LseVjWES7goy/TSb/4uSJkaQxCrDeo+RCVqUzJq1YLDos01RHlBq2GLS A8fuVnVfaNpaRnYwjdbHUYR1XvtwrdHkV5TBE= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:date:message-id:to:cc:subject:from:in-reply-to:references :x-mailer:mime-version:content-type:content-transfer-encoding; b=WUm1UlgrbHUM1UZ56ykq81uG+4m/kLJ7HLwebB6t1vyp/mz4Q8367Nz3RV+gDJMNc1 gH2SE6RCG0Zc4Yq1pyyJgTFIphHr2rkk562/9FK9bZreyhAbRBKR5cfsybCYnj9SQWir U5lywiOH1+PeZpMUQxLztIqYxtp3a723LimpM= Received: by 10.150.119.26 with SMTP id r26mr4546417ybc.60.1271114680322; Mon, 12 Apr 2010 16:24:40 -0700 (PDT) Received: from localhost (rikad42.riken.jp [134.160.214.42]) by mx.google.com with ESMTPS id 9sm1215986yxf.65.2010.04.12.16.24.37 (version=SSLv3 cipher=RC4-MD5); Mon, 12 Apr 2010 16:24:39 -0700 (PDT) Sender: Maho NAKATA Date: Tue, 13 Apr 2010 08:24:35 +0900 (JST) Message-Id: <20100413.082435.787670930925495306.chat95@mac.com> To: lists@mawer.org From: Maho NAKATA In-Reply-To: References: <20100412.131213.4959786962516027.chat95@mac.com> X-Mailer: Mew version 6.3 on Emacs 23.1 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Cc: adrian@freebsd.org, freebsd-stable@freebsd.org Subject: Re: Only 70% of theoretical peak performance on FreeBSD 8/amd64, Corei7 920 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 12 Apr 2010 23:24:41 -0000 Hi Antony I think this is not the case. I tested TurboBoost on/off on Ubuntu, Got= oBLAS achieved 95% of theoretical perfomance for both cases. cf. http://www.intel.com/support/processors/sb/cs-023143.htm and http://blog.goo.ne.jp/nakatamaho/e/86c0f4ac529fd5b530454ed795e6b466= (written in Japanese, tho) Thanks From: Antony Mawer Subject: Re: Only 70% of theoretical peak performance on FreeBSD 8/amd6= 4, Corei7 920 Date: Mon, 12 Apr 2010 23:58:17 +1000 > This may well be the same sort of issue that was discussed in this th= read here: > = > http://lists.freebsd.org/pipermail/freebsd-hackers/2010-March/031= 004.html > = > In short, the Core i7 CPUs have a feature called "TurboBoost" where > the clock speed of one or more cores is boosted when other cores are > idle and in a C2 or C3 sleep status ... if the appropriate power > saving mode isn't active on the system (which I don't think FreeBSD > does by default?), the idle cores are never put into the appropriate > power saving state, and as a result TurboBoost never kicks in... > = > It _may_ be that Ubuntu configures this correctly whereas FreeBSD doe= s > not (out of the box)? > = > Of course it may be something else entirely, but worth checking out..= .= > = > --Antony > = > On Mon, Apr 12, 2010 at 7:31 PM, Adrian Chadd wr= ote: >> Of course, what would be helpful is actually figuring out what is >> going on rather than some conjecture. :) >> >> With what he said, tweaking memory allocation under FreeBSD and/or >> linux would change the performance characteristics and either valida= te >> or disprove his assumptions? >> >> >> Adrian >> >> On 12 April 2010 12:12, Maho NAKATA wrote: >>> Hi FreeBSD developers, >>> [the original article in Japanese can be found at >>> http://blog.goo.ne.jp/nakatamaho/e/b5f6fbc3cc6e1ac4947463eb1ca4eb0a= ] >>> >>> *Abstract* >>> I compared the peak performance of FreeBSD 8.0/amd64 and Ubuntu 9.1= 0 amd64 using dgemm >>> (a linear algebra routine, matrix-matrix multiplication). >>> I obtained only 70% of theoretical peak performance on FreeBSD 8/am= d64 and >>> almost 95% on Ubuntu 9.10 /amd64. I'm really disappointed. >>> >>> *Introduction* >>> I'm a friend of Gotoh Kazushige, the principal developers of GotoBL= AS. He told me that >>> FreeBSD is not suitable OS for scientific computing or high perform= ance computing. He says >>> (in Japanese and my translation): >>> >>>> I guess FreeBSD does page coloring, but I don't think FreeBSD cons= iders very large cache >>>> size which recent CPU has. Support of a very large cache on Linux = is still not very will >>>> sophisticated, but on *BSDs, its worst; they uses too fine memory = allocation method, >>>> so we cannot expect large continuous physical memory allocation. >>>> Moreover, process scheduling is not so nice as *BSD employs an alg= orithm that >>>> changes physical CPUs in turn instead of allocating one core for s= uch kind of jobs. >>>> Take your own benchmark, and you'll see.. >>> >>> *Result* >>> Machine: Core i7 920 (42.56-44.8Gflops) / DDR3 1066 >>> OS: FreeBSD 8.0/amd64 and Ubuntu 9.10 >>> GotoBLAS2: 1.13 >>> >>> dgemm result >>> OS =A0 =A0 =A0: FLOPS =A0 =A0 =A0 =A0 =A0 : percent in peak >>> FreeBSD : 32.0 GFlops =A0 =A0 : 71% >>> Ubuntu =A0: 42.0-42.7GFlops : 93.8%-95.3% >>> >>> Thanks, >>> -- Nakata Maho http://accc.riken.jp/maho/ , http://ja.openoffice.or= g/ >>> =A0 Nakata Maho's PGP public keys: http://accc.riken.jp/maho/maho.p= gp.txt >>> >>> >>> >>> >>> _______________________________________________ >>> freebsd-stable@freebsd.org mailing list >>> http://lists.freebsd.org/mailman/listinfo/freebsd-stable >>> To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebs= d.org" >>> >> _______________________________________________ >> freebsd-stable@freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-stable >> To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd= .org" >> > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.= org" > =