From owner-freebsd-smp@FreeBSD.ORG Mon Sep 27 13:33:05 2004 Return-Path: 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 3F55016A4CE for ; Mon, 27 Sep 2004 13:33:05 +0000 (GMT) Received: from exchange.sandvine.com (sandvine.com [199.243.201.138]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9123943D46 for ; Mon, 27 Sep 2004 13:33:04 +0000 (GMT) (envelope-from ddolson@sandvine.com) X-MimeOLE: Produced By Microsoft Exchange V6.0.6556.0 content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Date: Mon, 27 Sep 2004 09:33:00 -0400 Message-ID: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: "Kernel Hacking"/Developing on a HT CPU versus "physical" CPUs Thread-Index: AcSkM/WwYHX6oaa3TrS1HLgEhrq4OAAYgshw From: "Dave Dolson" To: , Subject: RE: "Kernel Hacking"/Developing on a HT CPU versus "physical" CPUs X-BeenThere: freebsd-smp@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: FreeBSD SMP implementation group List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 27 Sep 2004 13:33:05 -0000 Here is one example: If you have dual HT processors, this looks like 4 CPUs to the O/S. For performance reasons, the scheduler should not treat them equally. =20 If there are two threads to run, they should be put on different = physical processors (vs. two hyperthreads of the same processor). David Dolson (ddolson@sandvine.com, www.sandvine.com) > -----Original Message----- > From: owner-freebsd-smp@freebsd.org > [mailto:owner-freebsd-smp@freebsd.org]On Behalf Of > mre2007@cs.columbia.edu > Sent: Saturday, September 25, 2004 10:48 AM > To: freebsd-smp@freebsd.org > Subject: "Kernel Hacking"/Developing on a HT CPU versus=20 > "physical" CPUs >=20 >=20 > Hey, I was wondering if from a developing/"kernel hacking"=20 > standpoint, are > hyperthreading and two "physical" CPUs any different? At what=20 > point do the > differences have to be taken into consideration when working on the > FreeBSD kernel/scheduler/etc? I'm looking to start contributing to the > FreeBSD project and am trying to get some hardware set aside. >=20 > Thanks! > -Marc > _______________________________________________ > freebsd-smp@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-smp > To unsubscribe, send any mail to "freebsd-smp-unsubscribe@freebsd.org" >=20