From owner-freebsd-arch@FreeBSD.ORG Fri Mar 26 15:17:07 2004 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 028D616A4CE; Fri, 26 Mar 2004 15:17:07 -0800 (PST) Received: from mtaw4.prodigy.net (mtaw4.prodigy.net [64.164.98.52]) by mx1.FreeBSD.org (Postfix) with ESMTP id E609043D45; Fri, 26 Mar 2004 15:17:06 -0800 (PST) (envelope-from kris@obsecurity.org) Received: from obsecurity.dyndns.org (780e70e64c084c0dc03a45a91a1b1b2c@adsl-67-115-73-128.dsl.lsan03.pacbell.net [67.115.73.128]) by mtaw4.prodigy.net (8.12.10/8.12.10) with ESMTP id i2QNGZfG022805; Fri, 26 Mar 2004 15:16:39 -0800 (PST) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id 5F98F5267B; Fri, 26 Mar 2004 15:16:35 -0800 (PST) Date: Fri, 26 Mar 2004 15:16:35 -0800 From: Kris Kennaway To: John Baldwin Message-ID: <20040326231635.GA91340@xor.obsecurity.org> References: <200403260230.i2Q2UTNZ097932@green.homeunix.org> <20040326.113751.14204546.imp@bsdimp.com> <200403261404.57741.jhb@FreeBSD.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="d6Gm4EdcadzBjdND" Content-Disposition: inline In-Reply-To: <200403261404.57741.jhb@FreeBSD.org> User-Agent: Mutt/1.4.2.1i cc: arch@freebsd.org cc: das@freebsd.org cc: tanimura@tanimura.dyndns.org cc: des@des.no Subject: Re: Is MTX_CONTESTED evil? X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 26 Mar 2004 23:17:07 -0000 --d6Gm4EdcadzBjdND Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Mar 26, 2004 at 02:04:57PM -0500, John Baldwin wrote: > On Friday 26 March 2004 01:37 pm, M. Warner Losh wrote: > > In message: > > > > des@des.no (Dag-Erling Sm?rgrav) writes: > > : "Brian F. Feldman" writes: > > : > Well, that certainly explains the blitz of crashes I had to fix > > : > recently! Since INVARIANTS and WITNESS are on by default, it would > > : > make sense to make ADAPTIVE_MUTEX default to catch more bugs. > > : > > : Making ADAPTIVE_MUTEXES default will not catch more bugs, it will just > > : piss off users. > > > > I think that if we don't fix the class of bugs that AM points out, > > we'll ruin our reputation as a quality system in the long run. Maybe > > they are so pervasive that we don't want to turn it on by default just > > yet, but there will come a time we turn it on, just like we turned on > > WITNESS and INVARIANTS to get better coverage on our testing. >=20 > Right, let's not just gratuitously break everyone right yet. It's actual= ly an=20 > option largely b/c I want us to be able to benchmark it once our locking = is=20 > farther along to see if it helps more than it hurts. FYI, I'm going to run with this on the bento cluster for a bit to dig out some of these bugs. Kris --d6Gm4EdcadzBjdND Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (FreeBSD) iD8DBQFAZLnSWry0BWjoQKURArDUAJ46SbMSJ7n09fOkq4xLI2v+UumqbgCgr6VR z2aA1EdivOoO71pvYyqLF7c= =Vq/L -----END PGP SIGNATURE----- --d6Gm4EdcadzBjdND--