From owner-freebsd-questions@FreeBSD.ORG Wed Aug 30 17:47:43 2006 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id CF11D16A4E7 for ; Wed, 30 Aug 2006 17:47:43 +0000 (UTC) (envelope-from skylar@cs.earlham.edu) Received: from quark.cs.earlham.edu (cs.earlham.edu [159.28.230.3]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9D81543D46 for ; Wed, 30 Aug 2006 17:47:34 +0000 (GMT) (envelope-from skylar@cs.earlham.edu) Received: from [128.95.231.218] (angband.gs.washington.edu [128.95.231.218]) (authenticated bits=0) by quark.cs.earlham.edu (8.13.6/8.13.3) with ESMTP id k7UHlK0v052446 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 30 Aug 2006 13:47:22 -0400 (EDT) (envelope-from skylar@cs.earlham.edu) X-Authentication-Warning: quark.cs.earlham.edu: Host angband.gs.washington.edu [128.95.231.218] claimed to be [128.95.231.218] Message-ID: <44F5CF0E.9020700@cs.earlham.edu> Date: Wed, 30 Aug 2006 10:46:54 -0700 From: Skylar Thompson Organization: Earlham College Computer Science Department User-Agent: Mail/News 1.5.0.5 (X11/20060728) MIME-Version: 1.0 To: Jordi Carrillo References: <94ff3700608301020l34251166nbdb4d72842e1bb86@mail.gmail.com> In-Reply-To: <94ff3700608301020l34251166nbdb4d72842e1bb86@mail.gmail.com> X-Enigmail-Version: 0.94.0.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig487ADC619E7AD80871E27A8E" X-Greylist: Sender succeded SMTP AUTH authentication, not delayed by milter-greylist-1.6 (quark.cs.earlham.edu [159.28.230.3]); Wed, 30 Aug 2006 13:47:27 -0400 (EDT) X-Virus-Scanned: ClamAV 0.88.2/1623/Wed Jul 26 18:35:11 2006 on quark.cs.earlham.edu X-Virus-Status: Clean X-Scanned-By: MIMEDefang 2.56 on 159.28.230.3 X-Spam-Status: No, score=-2.5 required=8.0 tests=AWL,BAYES_00 autolearn=ham version=3.1.3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on quark.cs.earlham.edu Cc: freebsd-questions@freebsd.org Subject: Re: SMP detection X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: skylar@cs.earlham.edu List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 30 Aug 2006 17:47:43 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig487ADC619E7AD80871E27A8E Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Jordi Carrillo wrote: > I've read that SMP should be disabled for performance issues (I did > not know > that before installing freebsd). I have a P4 3GHz with hyperthreading > technology. I have the SMP-GENERIC kernel and it only launches one > cpu. So, > I've decided to disable SMP from BIOS. Is that ok?, knowing that I have= a > Smp enabled kernel? or should I install one without smp? If so, is > there a > way to install one already precompiled? > Thanks in advance > I believe that HTT was disabled in FreeBSD per security report FreeBSD-SA-05:09.htt (http://security.freebsd.org/advisories/FreeBSD-SA-05:09.htt.asc). If you want to enable, I believe you can set the loader.conf option machdep.hlt_logical_cpus to 2. Having SMP enabled on a uniprocessor box shouldn't give you any stability problems, but SMP does use a different locking mechanism that can affect performance. You will probably get slightly better performance if you run with an SMP-disabled kernel. --=20 -- Skylar Thompson (skylar@cs.earlham.edu) -- http://www.cs.earlham.edu/~skylar/ --------------enig487ADC619E7AD80871E27A8E Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (SunOS) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFE9c8Qsc4yyULgN4YRAjmuAJ97hk0s6o3hvZwW0w7mnlhXd61slwCggxE/ QTa2GUOmwlPdHMXsJ4W+dmg= =PBGK -----END PGP SIGNATURE----- --------------enig487ADC619E7AD80871E27A8E--