From owner-freebsd-stable@FreeBSD.ORG Thu Sep 14 05:01:37 2006 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id B3BA916A40F for ; Thu, 14 Sep 2006 05:01:37 +0000 (UTC) (envelope-from kris@obsecurity.org) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8031A43D5D for ; Thu, 14 Sep 2006 05:01:35 +0000 (GMT) (envelope-from kris@obsecurity.org) Received: from obsecurity.dyndns.org (elvis.mu.org [192.203.228.196]) by elvis.mu.org (Postfix) with ESMTP id 10DC01A3C20; Wed, 13 Sep 2006 22:01:35 -0700 (PDT) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id 5E55B5134B; Thu, 14 Sep 2006 01:01:33 -0400 (EDT) Date: Thu, 14 Sep 2006 01:01:33 -0400 From: Kris Kennaway To: Gary Kline Message-ID: <20060914050133.GA26618@xor.obsecurity.org> References: <200609130905.k8D95idk062789@lurza.secnetix.de> <4507CC9B.60704@sun-fish.com> <20060913234934.GA92067@thought.org> <45089D47.6070005@uts.edu.au> <20060914045725.GB92358@thought.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="2oS5YaxWCcQjTEyO" Content-Disposition: inline In-Reply-To: <20060914045725.GB92358@thought.org> User-Agent: Mutt/1.4.2.2i Cc: Tony Maher , freebsd-stable@freebsd.org, Stefan Lambrev Subject: Re: optimization levels for 6-STABLE build{kernel,world} 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: Thu, 14 Sep 2006 05:01:37 -0000 --2oS5YaxWCcQjTEyO Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Sep 13, 2006 at 09:57:25PM -0700, Gary Kline wrote: > On Thu, Sep 14, 2006 at 10:07:35AM +1000, Tony Maher wrote: > > Gary Kline wrote: > >=20 > > > > > > > > > A couple of things. Will having gcc unroll loops have any > > > negative consequences? (I can't imagine how:: but better=20 > > > informed than to have something crash inexplicability.) > > > With 6.X safe at -O2 and with -funroll-loops, that should be > > > a slight gain, right? (It also will make an upgrade from 5.5=20 > > > to 6.[12] that much more rational.) > >=20 > > -funroll-loops affect loader see > > http://lists.freebsd.org/pipermail/freebsd-stable/2006-September/028145= .html > >=20 >=20 > Right. This is probably what Chuck Swiger was talking about. > I've never had this problems on my 5.[345] releases. And not > with 6.1 (knock-wood!!).=20 >=20 > I've just upgraded to -RELEASE and going to rebuild overnight on > the server that traped out. With -funroll-loops gone :-) Just leave it alone unless you know what you're doing...fiddling with the compiler flags just isn't going to give you a secret performance boost for general workloads, no matter how cool it might make you feel :) Kris --2oS5YaxWCcQjTEyO Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (FreeBSD) iD8DBQFFCOIsWry0BWjoQKURAjp+AKD7LQQZMDV0Vz/FyxStvzRqu+MAAwCgyweA GC93zK7LS0GR7YX3k9G6vrs= =gYjq -----END PGP SIGNATURE----- --2oS5YaxWCcQjTEyO--