From owner-freebsd-stable@FreeBSD.ORG Fri Dec 16 22:16:54 2011 Return-Path: Delivered-To: freebsd-stable@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3A53C1065673 for ; Fri, 16 Dec 2011 22:16:54 +0000 (UTC) (envelope-from talon@lpthe.jussieu.fr) Received: from shiva.jussieu.fr (shiva.jussieu.fr [134.157.0.129]) by mx1.freebsd.org (Postfix) with ESMTP id 9685C8FC16 for ; Fri, 16 Dec 2011 22:16:53 +0000 (UTC) Received: from parthe.lpthe.jussieu.fr (parthe.lpthe.jussieu.fr [134.157.10.1]) by shiva.jussieu.fr (8.14.4/jtpda-5.4) with ESMTP id pBGMGQMp075242 ; Fri, 16 Dec 2011 23:16:39 +0100 (CET) X-Ids: 165 Received: from [192.168.1.101] (sge91-2-82-227-32-26.fbx.proxad.net [82.227.32.26]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (Client did not present a certificate) by parthe.lpthe.jussieu.fr (Postfix) with ESMTPSA id 107FA1FEEA; Fri, 16 Dec 2011 23:16:24 +0100 (CET) Mime-Version: 1.0 (Apple Message framework v1251.1) From: Michel Talon In-Reply-To: <4EEBBD5E.50603@FreeBSD.org> Date: Fri, 16 Dec 2011 23:16:24 +0100 Message-Id: <91A8A86F-4D83-4C6F-8E27-B74204C6ACF9@lpthe.jussieu.fr> References: <1350C7A0-BE58-4C34-804A-A6A3C1C61761@lpthe.jussieu.fr> <4EEBBD5E.50603@FreeBSD.org> To: Doug Barton X-Mailer: Apple Mail (2.1251.1) X-Miltered: at jchkmail.jussieu.fr with ID 4EEBC33A.000 by Joe's j-chkmail (http : // j-chkmail dot ensmp dot fr)! X-j-chkmail-Enveloppe: 4EEBC33A.000/134.157.10.1/parthe.lpthe.jussieu.fr/parthe.lpthe.jussieu.fr/ Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-stable@FreeBSD.org Subject: Re: switching schedulers (Re: SCHED_ULE should not be the default) 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: Fri, 16 Dec 2011 22:16:54 -0000 Le 16 d=E9c. 2011 =E0 22:51, Doug Barton a =E9crit : > On 12/16/2011 13:40, Michel Talon wrote: >> Adrian Chadd said: >>=20 >>=20 >>> Hi all, >>>=20 >>> Can someone load a kernel module dynamically at boot-time? >>>=20 >>> Ie, instead of compiling it in, can 4bsd/ule be loaded as a KLD at=20= >>> boot-time, so the user can just change by rebooting? >>>=20 >>> That may be an acceptable solution for now. >>=20 >> As Luigi explained, the problem is not to have code for both >> schedulers residing in the kernel, the problem is to migrate >> processes from one scheduler to the other. >=20 > I think dynamically switching schedulers on a running system and = loading > one or the other at boot time are different problems, are they not? >=20 Of course, you are perfectly right., and i had misunderstood Adrian's = post. But if the problem is only to change scheduler by rebooting, i think it is no more expensive to compile a kernel with the other = scheduler. Or is it that people never compile kernels nowadays? The ability to switch scheduler on a = running machine would certainly be a more desirable way to test the best adaptation of = the system to the load. To come back to the problems in question about ULE i must say i don't = see obvious=20 malfunctions for my own use (i had some problems of this sort long ago, = but they disappeared with more recent FreeBSD). >=20 > Doug >=20 >=20 -- Michel Talon talon@lpthe.jussieu.fr