From owner-freebsd-smp@FreeBSD.ORG Thu Mar 12 17:14:54 2009 Return-Path: Delivered-To: freebsd-smp@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A41AA106564A for ; Thu, 12 Mar 2009 17:14:54 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id 7461C8FC0C for ; Thu, 12 Mar 2009 17:14:54 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (pool-98-109-39-197.nwrknj.fios.verizon.net [98.109.39.197]) by cyrus.watson.org (Postfix) with ESMTPSA id 043BA46B2A; Thu, 12 Mar 2009 13:14:53 -0400 (EDT) Received: from localhost (john@localhost [127.0.0.1]) (authenticated bits=0) by server.baldwin.cx (8.14.3/8.14.3) with ESMTP id n2CHEl28050967; Thu, 12 Mar 2009 13:14:47 -0400 (EDT) (envelope-from jhb@freebsd.org) From: John Baldwin To: won.derick@yahoo.com Date: Thu, 12 Mar 2009 10:55:22 -0400 User-Agent: KMail/1.9.7 References: <418159.62247.qm@web45804.mail.sp1.yahoo.com> In-Reply-To: <418159.62247.qm@web45804.mail.sp1.yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Message-Id: <200903121055.23408.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 Mar 2009 13:14:48 -0400 (EDT) X-Virus-Scanned: ClamAV 0.94.2/9101/Thu Mar 12 11:30:26 2009 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: robert@heron.pl, freebsd-smp@freebsd.org Subject: Re: only one logical CPU used in Xeon 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 Mar 2009 17:14:54 -0000 On Thursday 12 March 2009 10:28:15 am won.derick@yahoo.com wrote: >=20 > --- On Thu, 3/12/09, John Baldwin wrote: > >=20 > > -----Inline Attachment Follows----- > >=20 > > On Wednesday 11 March 2009 11:01:51 > > am Oliver Fromme wrote: > > > Here's how you can see the details in the demsg > > output: > > > The older machine: > > >=20 > > >=A0 > Features =3D 0xbfebfbff <...,HTT,...> > > >=20 > > > The "HTT" bit in the features bitmask indicates that > > the > > > processor supports hyperthreading. > >=20 > > No, that flag just means it supports a register where you > > can ask for the=20 > > total number of threads/cores per package.=A0 Multi-core > > CPUs that don't have=20 > > hyperthreads have 'HTT' set, but when you read the > > registers properly you see=20 > > that they have 1 thread per core. > >=20 >=20 > Does this mean that the # of logical CPUs per core is not enough to=20 determine whether the machine supports hyperthreading or not? You've said=20 earlier that the newer machine is not hyperthreaded, so I'm assuming that=20 there is another part in the dmesg output that says so. more guidance pls. Your new machine might be hyperthreaded. I'm not really sure as it's a P4 descendant and I'm not sure if Intel released some dual-core P4 Xeon that had 2 threads per core. The current Core processors do not implement multi= ple=20 threads in their cores, but neither of your systems have those CPUs. =2D-=20 John Baldwin