From owner-freebsd-stable@FreeBSD.ORG Fri Mar 28 18:05:48 2003 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 45A3C37B401 for ; Fri, 28 Mar 2003 18:05:48 -0800 (PST) Received: from fish.ish.com.au (212-86.dsl.connexus.net.au [203.17.212.86]) by mx1.FreeBSD.org (Postfix) with ESMTP id AE8AF43F3F for ; Fri, 28 Mar 2003 18:05:46 -0800 (PST) (envelope-from ari@ish.com.au) Received: from [203.29.62.130] (helo=ish.com.au) by fish.ish.com.au with esmtp (Exim 6.66 #1) id 18z5j2-0005dy-00 for freebsd-stable@freebsd.org; Sat, 29 Mar 2003 13:05:40 +1100 Date: Sat, 29 Mar 2003 13:05:39 +1100 Content-Type: text/plain; charset=US-ASCII; format=flowed Mime-Version: 1.0 (Apple Message framework v551) From: Aristedes Maniatis To: freebsd-stable@freebsd.org Content-Transfer-Encoding: 7bit In-Reply-To: <20030328104638.T208@freebsdmall.com> Message-Id: X-Mailer: Apple Mail (2.551) X-Scanner: exiscan *18z5j2-0005dy-00*IPBFTbAgpC.* on Astaro Security Linux Subject: 4.8 hyperthreading changes X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 29 Mar 2003 02:05:49 -0000 From the 4.8 changes page I found this: > FreeBSD now has rudimentary support for HyperThreading (HTT). SMP > kernels with the HTT kernel option will detect and start up the > logical processors on HTT-capable machines. The logical processors > will be treated like additional physical processors for the purposes > of process scheduling. On the 4.7 deployment systems I am running I have dual Xeon CPUs with hyperthreading. They appear as 4 CPUs in 'top'. That would seems to indicate to me that FreeBSD is scheduling them as four separate processors, however the note from: http://www.freebsd.org/relnotes/4-STABLE/relnotes/i386/x19.html#KERNEL makes it seem like this is a new 4.8 feature. Should I be concerned about upgrading when 4.8 is released in order to obtain the benefits of better use of these CPUs? Ari Maniatis --------------------------> ish group pty ltd 7 Darghan St Glebe 2037 Australia phone +61 2 9660 1400 fax +61 2 9660 7400 http www.ish.com.au | email info@ish.com.au PGP fingerprint 08 57 20 4B 80 69 59 E2 A9 BF 2D 48 C2 20 0C C8