From owner-freebsd-stable@FreeBSD.ORG  Sat May 13 01:58:10 2006
Return-Path: <owner-freebsd-stable@FreeBSD.ORG>
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 DF32616A402;
	Sat, 13 May 2006 01:58:10 +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 990F843D48;
	Sat, 13 May 2006 01:58:10 +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 7A8661A4E40;
	Fri, 12 May 2006 18:58:10 -0700 (PDT)
Received: by obsecurity.dyndns.org (Postfix, from userid 1000)
	id 9C49051B01; Fri, 12 May 2006 21:58:09 -0400 (EDT)
Date: Fri, 12 May 2006 21:58:09 -0400
From: Kris Kennaway <kris@obsecurity.org>
To: Dmitry Pryanishnikov <dmitry@atlantis.dp.ua>
Message-ID: <20060513015809.GA18438@xor.obsecurity.org>
References: <20060427160536.M96305@atlantis.atlantis.dp.ua>
	<20060502181118.M92256@fledge.watson.org>
	<20060512232806.Q35558@atlantis.atlantis.dp.ua>
Mime-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha1;
	protocol="application/pgp-signature"; boundary="KsGdsel6WgEHnImy"
Content-Disposition: inline
In-Reply-To: <20060512232806.Q35558@atlantis.atlantis.dp.ua>
User-Agent: Mutt/1.4.2.1i
Cc: freebsd-stable@FreeBSD.org, Robert Watson <rwatson@FreeBSD.org>
Subject: Re: RELENG_4 -> 5 -> 6: significant performance regression
X-BeenThere: freebsd-stable@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Production branch of FreeBSD source code <freebsd-stable.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>, 
	<mailto:freebsd-stable-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-stable>
List-Post: <mailto:freebsd-stable@freebsd.org>
List-Help: <mailto:freebsd-stable-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>,
	<mailto:freebsd-stable-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sat, 13 May 2006 01:58:11 -0000


--KsGdsel6WgEHnImy
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Fri, May 12, 2006 at 11:32:44PM +0300, Dmitry Pryanishnikov wrote:
>=20
> Hello!
>=20
> On Tue, 2 May 2006, Robert Watson wrote:
> >>options 	INVARIANTS
> >>options 	INVARIANT_SUPPORT
> >
> >In FreeBSD 5.x and FreeBSD 6.x, the INVARIANTS option has been=20
> >significantly expanded to test a much larger set of invariants, and also=
=20
> >incorporate kernel use-after-free checking, which involves memory=20
> >scrubbing.  This is great for catching bugs, but it will have a=20
> >significant performance impact, especially for kernel-intensive loads.
>=20
>  So maybe it's time to add, say,
>=20
> options      INVARIANTS_EXTENDED
>=20
> for these new and expensive checks, and leave only basic and cheap (yet
> effective for bug hunting) asserts enabled when only
>=20
> options      INVARIANTS
>=20
> is defined?

No, they are all effective for bug hunting.  You just need to be aware
that it is incompatible with performance.

Kris

--KsGdsel6WgEHnImy
Content-Type: application/pgp-signature
Content-Disposition: inline

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.3 (FreeBSD)

iD8DBQFEZT0xWry0BWjoQKURAsQxAKDQaF/Q7mL5aMt4a45MqKDmhgBP+wCg82BL
nSYJ3OooAiLI8E4E8a15QLY=
=ujRL
-----END PGP SIGNATURE-----

--KsGdsel6WgEHnImy--