From owner-freebsd-current Sun Mar 2 11:14:42 2003 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 6725137B401 for <current@freebsd.org>; Sun, 2 Mar 2003 11:14:41 -0800 (PST) Received: from heron.mail.pas.earthlink.net (heron.mail.pas.earthlink.net [207.217.120.189]) by mx1.FreeBSD.org (Postfix) with ESMTP id F3F3043FA3 for <current@freebsd.org>; Sun, 2 Mar 2003 11:14:40 -0800 (PST) (envelope-from tlambert2@mindspring.com) Received: from pool0246.cvx22-bradley.dialup.earthlink.net ([209.179.198.246] helo=mindspring.com) by heron.mail.pas.earthlink.net with asmtp (SSLv3:RC4-MD5:128) (Exim 3.33 #1) id 18pYuv-0006IO-00; Sun, 02 Mar 2003 11:14:35 -0800 Message-ID: <3E6257B1.32AB9644@mindspring.com> Date: Sun, 02 Mar 2003 11:12:49 -0800 From: Terry Lambert <tlambert2@mindspring.com> X-Mailer: Mozilla 4.79 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Poul-Henning Kamp <phk@phk.freebsd.dk> Cc: Bruce Evans <bde@zeta.org.au>, "M. Warner Losh" <imp@bsdimp.com>, current@FreeBSD.ORG Subject: Re: Any ideas why we can't even boot a i386 ? References: <9064.1046627721@critter.freebsd.dk> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-ELNK-Trace: b1a02af9316fbb217a47c185c03b154d40683398e744b8a40e82b3f33a558e7c588d970fa3516a6393caf27dac41a8fd350badd9bab72f9c350badd9bab72f9c Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: <freebsd-current.FreeBSD.ORG> List-Archive: <http://docs.freebsd.org/mail/> (Web Archive) List-Help: <mailto:majordomo@FreeBSD.ORG?subject=help> (List Instructions) List-Subscribe: <mailto:majordomo@FreeBSD.ORG?subject=subscribe%20freebsd-current> List-Unsubscribe: <mailto:majordomo@FreeBSD.ORG?subject=unsubscribe%20freebsd-current> X-Loop: FreeBSD.ORG Poul-Henning Kamp wrote: > In message <20030303034332.Y30986-100000@gamplex.bde.org>, Bruce Evans writes: > >On Sun, 2 Mar 2003, Bruce Evans wrote: > >> On Fri, 28 Feb 2003, Poul-Henning Kamp wrote: > >> > My main concern would be if the chips have the necessary "umphf" > >> > to actually do a real-world job once they're done running all the > >> > overhead of 5.0-R. The lack of cmpxchg8 makes the locking horribly > >> > expensive. > >> > >> Actually, the lack of cmpxchg8 only makes locking more expensive. It's > > > >I.e., strictly more expensive, but not much more. > > Bruce, it is not a matter of the relative expensiveness of the various > implementations of locking primitives, its a matter of the cummulative > weight of all the locks we add to the system. Bruce's "make world" benchmark gave coverage of the cumulative weight, in support of his point. -- Terry To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message