From owner-freebsd-current@FreeBSD.ORG Thu Aug 25 16:34:28 2005 Return-Path: X-Original-To: freebsd-current@FreeBSD.org Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 453D616A41F for ; Thu, 25 Aug 2005 16:34:28 +0000 (GMT) (envelope-from bohra@cs.rutgers.edu) Received: from mailer.nec-labs.com (mailer.nec-labs.com [138.15.108.3]) by mx1.FreeBSD.org (Postfix) with ESMTP id DD0A643D53 for ; Thu, 25 Aug 2005 16:34:27 +0000 (GMT) (envelope-from bohra@cs.rutgers.edu) Received: from [138.15.104.242] ([138.15.104.242] unverified) by mailer.nec-labs.com with Microsoft SMTPSVC(5.0.2195.6713); Thu, 25 Aug 2005 12:34:26 -0400 Message-ID: <430DF37F.80209@cs.rutgers.edu> Date: Thu, 25 Aug 2005 12:36:15 -0400 From: Aniruddha Bohra User-Agent: Mozilla Thunderbird 1.0.2 (X11/20050426) X-Accept-Language: en-us, en MIME-Version: 1.0 To: "Justin R. Smith" References: <430DF217.2020908@drexel.edu> In-Reply-To: <430DF217.2020908@drexel.edu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 25 Aug 2005 16:34:26.0953 (UTC) FILETIME=[DBE5FF90:01C5A992] Cc: freebsd-current@FreeBSD.org Subject: Re: Hyperthreading degrades performance? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 25 Aug 2005 16:34:28 -0000 Justin R. Smith wrote: >This is in reply to the people who said this because of >cache-contention. Has anyone benchmarked this? > > See the following : Evaluating the Impact of Simultaneous Multithreading on Network Servers Using Real Hardware Yaoping Ruan, Vivek S. Pai, Erich Nahum, and John Tracey /Proceedings of the 2005 ACM SIGMETRICS International Conference on Measurement & Modeling of Computer Systems (SIGMETRICS '05) http://www.cs.princeton.edu/~yruan/XeonSMT/smt.pdf They have an excellent discussion for a web server Cheers Aniruddha /