From owner-freebsd-current@FreeBSD.ORG Sun Oct 8 12:35:44 2006 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 41D6E16A492; Sun, 8 Oct 2006 12:35:44 +0000 (UTC) (envelope-from delphij@delphij.net) Received: from tarsier.geekcn.org (tarsier.geekcn.org [210.51.165.229]) by mx1.FreeBSD.org (Postfix) with ESMTP id BC2D643D5F; Sun, 8 Oct 2006 12:35:22 +0000 (GMT) (envelope-from delphij@delphij.net) Received: from localhost (tarsier.geekcn.org [210.51.165.229]) by tarsier.geekcn.org (Postfix) with ESMTP id 74E6CEB0A84; Sun, 8 Oct 2006 20:35:15 +0800 (CST) X-Virus-Scanned: amavisd-new at geekcn.org Received: from tarsier.geekcn.org ([210.51.165.229]) by localhost (mail.geekcn.org [210.51.165.229]) (amavisd-new, port 10024) with ESMTP id 0gh+Jppm2nLv; Sun, 8 Oct 2006 20:35:05 +0800 (CST) Received: from [10.217.12.40] (sina152-194.staff.sina.com.cn [61.135.152.194]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by tarsier.geekcn.org (Postfix) with ESMTP id 03D79EB0A79; Sun, 8 Oct 2006 20:35:01 +0800 (CST) DomainKey-Signature: a=rsa-sha1; s=default; d=delphij.net; c=nofws; q=dns; h=message-id:date:from:organization:user-agent:mime-version:to:cc: subject:references:in-reply-to:x-enigmail-version:content-type; b=ruK19W/pLHWAPvj0nQHTsmOS24yat0Xi8phgzDTQp8PDhCkuH10prDxMvjXElNqu7 GpAxv51KfAyb8OusKD13g== Message-ID: <4528F069.7040504@delphij.net> Date: Sun, 08 Oct 2006 20:34:49 +0800 From: LI Xin Organization: The FreeBSD Project User-Agent: Thunderbird 1.5.0.7 (Macintosh/20060909) MIME-Version: 1.0 To: Astrodog References: <2fd864e0610080423q7ba6bdeal656a223e662a5d@mail.gmail.com> <200610082011.53649.davidxu@freebsd.org> <2fd864e0610080516k6682c101i8d9b83578593fb28@mail.gmail.com> In-Reply-To: <2fd864e0610080516k6682c101i8d9b83578593fb28@mail.gmail.com> X-Enigmail-Version: 0.94.1.0 Content-Type: multipart/signed; micalg=pgp-ripemd160; protocol="application/pgp-signature"; boundary="------------enigAE293599FC1AC9FC6D056869" Cc: freebsd-current@freebsd.org, David Xu , current@freebsd.org Subject: Re: [PATCH] MAXCPU alterable in kernel config - needs testers X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 08 Oct 2006 12:35:44 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigAE293599FC1AC9FC6D056869 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Astrodog wrote: > On 10/8/06, David Xu wrote: >> On Sunday 08 October 2006 19:23, Astrodog wrote: >> > With the quad core processors coming out soon, this is going to beco= me >> > more of an issue.. (Sun T1/2000s aside). This is basically the same >> > patch from a few months ago, with updated offsets. >> > >> > If you don't define MAXCPU in the kernel config, it reverts to old >> > behavior. It has no logic to keep you from shooting yourself in the >> > foot though.. you can define options SMP and options MAXCPU 128 on >> > arm. >> > >> > --- Harrison Grundy >> >> I think MAXCPU should not be great than 32, since we currently define >> cpumask_t as an integer which now should be changed to a bitmap and >> a group of operations like we did for sigset_t. >> >> David Xu >> >=20 > Currently, MAXCPU is 16 on most platforms. In general, this value serves as a boundary of the kernel logic, and is determined by various factors, e.g., the bits available in cpumask_t, etc., therefore, I really do not see much benefit of letting this value customizable. Perhaps we can say that the problem is not that the value itself is immutable by the system administrator, but it was (perhaps?) not correctly reflected the actual support that the kernel can provide? Cheers, --=20 Xin LI http://www.delphij.net/ FreeBSD - The Power to Serve! --------------enigAE293599FC1AC9FC6D056869 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 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFFKPBpOfuToMruuMARAxolAJ9x+Rx7gZBHLELXbbKp48qG1LO1EQCfbpKP bo1MZ77WK6OczY8bAk8gCMM= =67j4 -----END PGP SIGNATURE----- --------------enigAE293599FC1AC9FC6D056869--