Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 17 Apr 2002 16:35:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 17 Apr 2002 16:35:05 -0400 Received: from mailsorter.ma.tmpw.net ([63.112.169.25]:23331 "EHLO mailsorter.ma.tmpw.net") by vger.kernel.org with ESMTP id ; Wed, 17 Apr 2002 16:35:04 -0400 Message-ID: <61DB42B180EAB34E9D28346C11535A78177F04@nocmail101.ma.tmpw.net> From: "Holzrichter, Bruce" To: "'Robert Love'" , "Martin J. Bligh" Cc: James Bourne , Ingo Molnar , linux-kernel@vger.kernel.org Subject: RE: Hyperthreading Date: Wed, 17 Apr 2002 15:34:46 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > On Wed, 2002-04-17 at 17:10, Martin J. Bligh wrote: > > > Total of 4 processors activated (14299.95 BogoMIPS). > > > > Before you get too excited about that, how much performance > boost do > > you actually get by turning on Hyperthreading? ;-) I've seen some Intel bench's and they are specing an increase of 0% to 30% (Though check Anandtech, he did a benchmark on his DB, and got a small performance Decrease on a test!) After looking at the Hyperthreading Doc's, It looks like they are trying to utilize some of the idle time the Execution engine has while waiting for other ops to happen, Trace code misses, and such. Strap on an extra processor state, and get some extra oomph. Hey, the P4 can use all the extra oomph it can get! B. - 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/