From owner-freebsd-stable@FreeBSD.ORG Wed May 3 18:50:06 2006 Return-Path: X-Original-To: freebsd-stable@freebsd.org 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 B2FCF16A416 for ; Wed, 3 May 2006 18:50:06 +0000 (UTC) (envelope-from kris@obsecurity.org) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5E33B43D46 for ; Wed, 3 May 2006 18:50:06 +0000 (GMT) (envelope-from kris@obsecurity.org) Received: from obsecurity.dyndns.org (elvis.mu.org [192.203.228.196]) by elvis.mu.org (Postfix) with ESMTP id 42AEE1A4D7B; Wed, 3 May 2006 11:50:06 -0700 (PDT) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id 9B5B0518DD; Wed, 3 May 2006 14:50:05 -0400 (EDT) Date: Wed, 3 May 2006 14:50:05 -0400 From: Kris Kennaway To: Vinny Abello Message-ID: <20060503185005.GA31387@xor.obsecurity.org> References: <20060503113955.U1147@ganymede.hub.org> <4458CE13.6060804@mac.com> <7.0.1.0.2.20060503132315.09da2cf8@tellurian.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="jRHKVT23PllUwdXP" Content-Disposition: inline In-Reply-To: <7.0.1.0.2.20060503132315.09da2cf8@tellurian.com> User-Agent: Mutt/1.4.2.1i Cc: freebsd-stable@freebsd.org Subject: Re: Hyperthreading in 6.x ... still frowned upon? X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 03 May 2006 18:50:07 -0000 --jRHKVT23PllUwdXP Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, May 03, 2006 at 01:36:04PM -0400, Vinny Abello wrote: > An Intel technical rep that gave a presentation on upcoming Intel VT=20 > technology in processors (Virtualization Technology) that I attended=20 > indicated that Hyperthreading was really designed to start getting=20 > programmers to program threading into their applications in=20 > preparation of dual core processors that we now have. That sounds like an interesting interpretation of history :-) > I typically disable Hyperthreading on all my servers as they are dual=20 > processor or dual core/dual processor or better anyway. I tend to get=20 > better results (with my applications) without Hyperthreading. I've=20 > been experimenting with leaving it on with my workstation as it's not=20 > a dual core or dual processor. In my experience it's almost always a net loss too. One should measure for oneself though. Kris --jRHKVT23PllUwdXP Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (FreeBSD) iD8DBQFEWPtdWry0BWjoQKURAt7jAJ4pZIeCIeUvMUHxI5BDulTOAnAcJQCfZXPF 8bEfR4BSuKbdDPcELnYvcdI= =N7Cp -----END PGP SIGNATURE----- --jRHKVT23PllUwdXP--