From owner-freebsd-net@FreeBSD.ORG Thu Jan 10 19:37:16 2013 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 09D43D31 for ; Thu, 10 Jan 2013 19:37:16 +0000 (UTC) (envelope-from peter@rulingia.com) Received: from vps.rulingia.com (host-122-100-2-194.octopus.com.au [122.100.2.194]) by mx1.freebsd.org (Postfix) with ESMTP id 9A082386 for ; Thu, 10 Jan 2013 19:37:14 +0000 (UTC) Received: from server.rulingia.com (c220-239-253-186.belrs5.nsw.optusnet.com.au [220.239.253.186]) by vps.rulingia.com (8.14.5/8.14.5) with ESMTP id r0AJb5MN095832 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 11 Jan 2013 06:37:05 +1100 (EST) (envelope-from peter@rulingia.com) X-Bogosity: Ham, spamicity=0.000000 Received: from server.rulingia.com (localhost.rulingia.com [127.0.0.1]) by server.rulingia.com (8.14.5/8.14.5) with ESMTP id r0AJb06K034573 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 11 Jan 2013 06:37:00 +1100 (EST) (envelope-from peter@server.rulingia.com) Received: (from peter@localhost) by server.rulingia.com (8.14.5/8.14.5/Submit) id r0AJax8q034572; Fri, 11 Jan 2013 06:36:59 +1100 (EST) (envelope-from peter) Date: Fri, 11 Jan 2013 06:36:59 +1100 From: Peter Jeremy To: Barney Cordoba Subject: Re: To SMP or not to SMP Message-ID: <20130110193659.GA27156@server.rulingia.com> References: <1357611958.66651.YahooMailClassic@web121603.mail.ne1.yahoo.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="2fHTh5uZTiUOsy+g" Content-Disposition: inline In-Reply-To: <1357611958.66651.YahooMailClassic@web121603.mail.ne1.yahoo.com> X-PGP-Key: http://www.rulingia.com/keys/peter.pgp User-Agent: Mutt/1.5.21 (2010-09-15) Cc: freebsd-net@freebsd.org X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 10 Jan 2013 19:37:16 -0000 --2fHTh5uZTiUOsy+g Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 2013-Jan-07 18:25:58 -0800, Barney Cordoba wr= ote: >I have a situation where I have to run 9.1 on an old single core >box. Does anyone have a handle on whether it's better to build a non >SMP kernel or to just use a standard SMP build with just the one >core? Another input for this decision is kern/173322. Currently on x86, atomic operations within kernel modules are implemented using calls to code in the kernel, which do or don't use lock prefixes depending on whethur the kernel was built as SMP. My proposed change changes kernel modules to inline atomic operations but always include lock prefixes (effectively reverting r49999). I'm appreciate anyone who feels like testing the impact of this change. --=20 Peter Jeremy --2fHTh5uZTiUOsy+g Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (FreeBSD) iEYEARECAAYFAlDvGFsACgkQ/opHv/APuIdc3QCgsCHQWw6JG2nFg0iWRQDfbWpQ X8kAnROz6oMevcQVqqGDs22nnj/3aFLW =K4kF -----END PGP SIGNATURE----- --2fHTh5uZTiUOsy+g--