From owner-freebsd-current@FreeBSD.ORG Thu Aug 25 18:32:44 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 2C1BB16A41F; Thu, 25 Aug 2005 18:32:44 +0000 (GMT) (envelope-from rwatson@FreeBSD.org) Received: from cyrus.watson.org (cyrus.watson.org [204.156.12.53]) by mx1.FreeBSD.org (Postfix) with ESMTP id 650D943D58; Thu, 25 Aug 2005 18:32:43 +0000 (GMT) (envelope-from rwatson@FreeBSD.org) Received: from fledge.watson.org (fledge.watson.org [204.156.12.50]) by cyrus.watson.org (Postfix) with ESMTP id E617946BB6; Thu, 25 Aug 2005 14:32:42 -0400 (EDT) Date: Thu, 25 Aug 2005 19:32:42 +0100 (BST) From: Robert Watson X-X-Sender: robert@fledge.watson.org To: Andre Oppermann In-Reply-To: <430E0ABA.7080600@freebsd.org> Message-ID: <20050825193221.R72462@fledge.watson.org> References: <430DF217.2020908@drexel.edu> <20050825173440.O16967@fledge.watson.org> <430E09F8.8090001@freebsd.org> <20050825191230.C16967@fledge.watson.org> <430E0ABA.7080600@freebsd.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: "Justin R. Smith" , 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 18:32:44 -0000 On Thu, 25 Aug 2005, Andre Oppermann wrote: > Robert Watson wrote: >> >> On Thu, 25 Aug 2005, Andre Oppermann wrote: >> >>> Don't forget better PIV revisions with larger instruction decoder caches, >>> better cache prefetching and branch prediction. I doubt much of the >>> improvement is due to our SMP changes. A real test to find out whether >>> it's our work or Intels would be to benchmark an old (pre Nacona) PIV >>> running 5.3R and 7.0-current vs. a new one doing the same. >> >> Well, given that my test box for this hasn't changed in three years, I >> think I can safely argue it's not the hardware :-). > > Ok, you win. :-) > > Then the effect of HTT should be much better if you would pop in one of > the latest PIV revisions. My test machine aside, I'm quite willing to believe the hardware has gotten better though. :-) Robert N M Watson