From owner-freebsd-smp@FreeBSD.ORG Thu Oct 12 14:08:35 2006 Return-Path: X-Original-To: freebsd-smp@freebsd.org Delivered-To: freebsd-smp@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 946E316A4D4 for ; Thu, 12 Oct 2006 14:08:35 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (66-23-211-162.clients.speedfactory.net [66.23.211.162]) by mx1.FreeBSD.org (Postfix) with ESMTP id 499CF43E78 for ; Thu, 12 Oct 2006 14:07:00 +0000 (GMT) (envelope-from jhb@freebsd.org) Received: from localhost.corp.yahoo.com (john@localhost [127.0.0.1]) (authenticated bits=0) by server.baldwin.cx (8.13.6/8.13.6) with ESMTP id k9CE6qIU005698; Thu, 12 Oct 2006 10:06:55 -0400 (EDT) (envelope-from jhb@freebsd.org) From: John Baldwin To: freebsd-smp@freebsd.org Date: Thu, 12 Oct 2006 09:24:48 -0400 User-Agent: KMail/1.9.1 References: <20061009114520.1355.qmail@web8608.mail.in.yahoo.com> <200610101543.29138.jhb@freebsd.org> <200610102015.36589.joao@matik.com.br> In-Reply-To: <200610102015.36589.joao@matik.com.br> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Message-Id: <200610120924.48482.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by milter-greylist-2.0.2 (server.baldwin.cx [127.0.0.1]); Thu, 12 Oct 2006 10:06:57 -0400 (EDT) X-Virus-Scanned: ClamAV 0.88.3/2026/Thu Oct 12 02:47:06 2006 on server.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-4.4 required=4.2 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=ham version=3.1.3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on server.baldwin.cx Cc: JoaoBR Subject: Re: Hyperthreading Issues (on Athlon64?) X-BeenThere: freebsd-smp@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: FreeBSD SMP implementation group List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 12 Oct 2006 14:08:35 -0000 On Tuesday 10 October 2006 19:15, JoaoBR wrote: > On Tuesday 10 October 2006 16:43, John Baldwin wrote: > > On Tuesday 10 October 2006 14:55, JoaoBR wrote: > > > On Tuesday 10 October 2006 15:11, Brooks Davis wrote: > > > > > My dmesg does not have the line about "Hyperthreading: 2 logical > > > > > CPUs", though. =A0But I had been pretty sure the Athlon64 chips d= idn't > > > > > have any hyperthreading support. =A0Why is the HTT there? > > > > > > HTT is NOT hyperthreading, HT is and HT does not exist on AMD64 > > > > Err, no. =A0The HTT there stands for HyperThreading Technology. >=20 > you say it right: "stands for" in this case >=20 > But I think it "is" the other way round, in terms of abreviation: >=20 > HTT =3D Hyper Transport Technology > HT =3D Hyper Threading (Technology) I don't think this really bothers anyone. > Even if this is certainly ok for whom knows it, then an AMD X2 is defini= tly=20 > not a hyperthreaded processor but has 2 cores as well as Intel's newer Co= re=20 > Duo, so HTT for an AMD X2 would be wrong (my opinion again) You didn't read anything I said earlier. When dual-core came out, to make = it easier for OS's to detect it (probably Windows), AMD made a dual-core CPU look just like an Intel CPU with 2 hyperthreads including using the CPUID HT flag in cpuid that _Intel_ had reserved. Even ports/misc/cpuid calls the flag HT. Sheesh. =2D-=20 John Baldwin