From owner-freebsd-arch@FreeBSD.ORG Sat Jun 11 20:17:12 2011 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id BBB25106564A; Sat, 11 Jun 2011 20:17:12 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from mail.zoral.com.ua (mx0.zoral.com.ua [91.193.166.200]) by mx1.freebsd.org (Postfix) with ESMTP id 364158FC0A; Sat, 11 Jun 2011 20:17:11 +0000 (UTC) Received: from deviant.kiev.zoral.com.ua (root@deviant.kiev.zoral.com.ua [10.1.1.148]) by mail.zoral.com.ua (8.14.2/8.14.2) with ESMTP id p5BKH35S008777 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sat, 11 Jun 2011 23:17:04 +0300 (EEST) (envelope-from kostikbel@gmail.com) Received: from deviant.kiev.zoral.com.ua (kostik@localhost [127.0.0.1]) by deviant.kiev.zoral.com.ua (8.14.4/8.14.4) with ESMTP id p5BKH3wD019296; Sat, 11 Jun 2011 23:17:03 +0300 (EEST) (envelope-from kostikbel@gmail.com) Received: (from kostik@localhost) by deviant.kiev.zoral.com.ua (8.14.4/8.14.4/Submit) id p5BKH33E019295; Sat, 11 Jun 2011 23:17:03 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: deviant.kiev.zoral.com.ua: kostik set sender to kostikbel@gmail.com using -f Date: Sat, 11 Jun 2011 23:17:03 +0300 From: Kostik Belousov To: Warner Losh Message-ID: <20110611201703.GO48734@deviant.kiev.zoral.com.ua> References: <4DF3B532.6020908@FreeBSD.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="YbCBl//VW3xXyIiK" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.3i X-Virus-Scanned: clamav-milter 0.95.2 at skuns.kiev.zoral.com.ua X-Virus-Status: Clean X-Spam-Status: No, score=-3.3 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00, DNS_FROM_OPENWHOIS autolearn=no version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on skuns.kiev.zoral.com.ua Cc: Adrian Chadd , Doug Barton , freebsd-arch@freebsd.org Subject: Re: [RFC] shipping kernels with default modules? X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 11 Jun 2011 20:17:12 -0000 --YbCBl//VW3xXyIiK Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, Jun 11, 2011 at 02:00:20PM -0600, Warner Losh wrote: >=20 > On Jun 11, 2011, at 12:34 PM, Doug Barton wrote: > > On 6/11/2011 2:21 AM, Adrian Chadd wrote: > >> Hi guys, > >>=20 > >> Has there been any further thought as of late about shipping kernels > >> with modules only by default, rather than monolithic kernels? > >>=20 > >> I tried this experiment a couple years ago and besides a little > >> trickery with ACPI module loading, it worked out fine. > >>=20 > >> Is there any reason we aren't doing this at the moment? Eg by having a > >> default loader modules list populated from the kernel config file? > >=20 > > Has anyone benchmarked monolithic vs. modular? I think that should be d= one before we move in this direction. >=20 > I haven't noticed a difference, but I haven't done any specific benchmark= ing. There might be some measurable difference on i386, where we use dso for modules. As a consequence, the overhead of GOT/PLT indirection, and, more important, stolen %ebx on the register-starved architecture, may make a difference. I doubt that any difference can be measured on amd64. --YbCBl//VW3xXyIiK Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (FreeBSD) iEYEARECAAYFAk3zzT8ACgkQC3+MBN1Mb4jOPQCfV62nloWb6iVteeZ5dGfMLLPJ BkoAn2hGp2Z6Qg6XxRbHa/I5Bzj6X8a3 =jA/5 -----END PGP SIGNATURE----- --YbCBl//VW3xXyIiK--