From owner-freebsd-arch@freebsd.org Wed Aug 26 17:20:11 2015 Return-Path: Delivered-To: freebsd-arch@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 3DD809C34F5 for ; Wed, 26 Aug 2015 17:20:11 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id 19B3EFC4 for ; Wed, 26 Aug 2015 17:20:11 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: by mailman.ysv.freebsd.org (Postfix) id 1716D9C34F4; Wed, 26 Aug 2015 17:20:11 +0000 (UTC) Delivered-To: arch@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id F0D219C34F3 for ; Wed, 26 Aug 2015 17:20:10 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from mail-pa0-f50.google.com (mail-pa0-f50.google.com [209.85.220.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id C9805FC3 for ; Wed, 26 Aug 2015 17:20:10 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: by pabzx8 with SMTP id zx8so76202108pab.1 for ; Wed, 26 Aug 2015 10:20:09 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:sender:from:content-type:subject:date:message-id :to:mime-version; bh=WwBdS4EPEGJeI/gxigw1UHgqWlnOJ6kQL46B3Q1Ymrg=; b=LOjJk4OT+TLB0zou1VuxAYFXKzt/60tojgNPAlArYbRfYyXr6eWl61TeWPWszQ3KHr duGA+Azxd8Sa3JOaouFTYmTfmw7dmq//FeAj9vgTj7W/qkYDI1V2yfwp906keN7cspRH nCh6y4Z7ajHzGfZy+AWtTi+QwkeMksffKGyZgimE58A1QuxdySWoOyuX1k1rGI/Qp+Kr BRzwSE24e39NKJAApzjjYZJLcmGIzNjuvUik0rSIzJGUvWsuRkqh1SJShsn0Z43vfawn Wg9YFyeLM91bydZVbsxiXP3lcpTYiEqJLwp5wySW57QwfO2NxWflSvy9Iip68wjWTl9Z glyQ== X-Gm-Message-State: ALoCoQn/xepedwWkyHCj2dnCwqjzBaNKlyi8K+W6gW3sIbzEjvi689kD10yQUvBjiuveDMF5zNzG X-Received: by 10.66.221.193 with SMTP id qg1mr62390596pac.103.1440609609342; Wed, 26 Aug 2015 10:20:09 -0700 (PDT) Received: from [100.127.144.155] ([69.53.245.35]) by smtp.gmail.com with ESMTPSA id b6sm25366058pdo.63.2015.08.26.10.20.08 for (version=TLS1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 26 Aug 2015 10:20:08 -0700 (PDT) Sender: Warner Losh From: Warner Losh X-Pgp-Agent: GPGMail 2.5 Content-Type: multipart/signed; boundary="Apple-Mail=_E012EBF8-BAA7-4B92-BCE8-E4C098D47E92"; protocol="application/pgp-signature"; micalg=pgp-sha512 Subject: exporting INVARIANTS easily Date: Wed, 26 Aug 2015 11:20:06 -0600 Message-Id: To: "freebsd-arch@freebsd.org" Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2102\)) X-Mailer: Apple Mail (2.2102) X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 26 Aug 2015 17:20:11 -0000 --Apple-Mail=_E012EBF8-BAA7-4B92-BCE8-E4C098D47E92 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 Greetings, Many of the performance eating features are exported via some kind of = sysctl, usually patterned after the case of witness as debug.foo. INVARIANTS isn=E2=80=99t= one of those features. https://reviews.freebsd.org/D3488 implements debug.invariants. Please comment. I=E2=80=99d thought about adding it to the kern.features sysctl, but = thought better of it since it isn=E2=80=99t a facility that people can use. If you include the kernel config in the kernel, you can get this = information via config -x | grep INVARIANTS but not all kernels do that. This is more robust. I also know that you can load some modules compiled INVARIANTS when the = base kernel isn=E2=80=99t built that way and this won=E2=80=99t reflect that. = There=E2=80=99s no good want to include that information and is an uncommon use case. Our use case? We have a raft of test machines. Most run without = INVARIANTS since we want to characterize the performance of the release under test. Some = are running INVARIANTS since we want to test the robustness as well, even at the = expense of some performance. To ensure we don=E2=80=99t accidentally include = INVARIANTS systems in the performance number, we=E2=80=99ve adding a key to an internal = database that=E2=80=99s driven off this sysctl. Comments? Warner --Apple-Mail=_E012EBF8-BAA7-4B92-BCE8-E4C098D47E92 Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Message signed with OpenPGP using GPGMail -----BEGIN PGP SIGNATURE----- Comment: GPGTools - https://gpgtools.org iQIcBAEBCgAGBQJV3fVGAAoJEGwc0Sh9sBEAfNIQALys9LOQgbaztLjuACdJe7NH gpVlHIbcrwAk6+hFmIEVOvRHbwryCoTpII4I2dQexD8Or3NEzXzCXhmzTXY91NQ8 ud/rR74JekcALMPP4MkX+qCY/OeoSsE6MOFepcrctRAeujZvDa6y7FLeyhl7acHr xBLSsr+mPk2IFgYImTaiEvcz3zZxVp2jentW8LoPSQGlnRguypqLgoSnZiRb5sow dIuk+Qt6iQhvqIXXzceJJj3bfDaMp52aeGKn02fq5oZDLRCD/SHs4wjUymMb5tP6 uUnF6zQz8bKcGmLf/3OqIzCm58lbMiif4rGN9BpgXpyMv7vd62tb3yIVruY3nV83 MTVMW2TfAqyyY9liZhFdQtHsoxKv/qXX8xXZjv56OU/VSvM53sT09Q+cVeVcY8d0 a00++wgwHyzl5Bqe5H+TPsOpNgUeE8Jfq24KxToqU21YCw+S/iPt6nVa3mCye4GQ 9PJaruTaSAvvFoE8PivAWTJ7Ro53bzIrKFyJDFjANIOr+zk61fd/YOuJ/LZZGD4E Je8MUKJEYKPk7YfQKrjcgEdC2+CQpUzlXSHaok7DXRdIwt8l7ozlUqL6/qobtj0W rAOJl4C4wBcZCITZGjL5qtFvBsPMdXCluhajsNtis4vZwQf3fyI022g6DY3osvCw XoV1XnTbuJNT3Rf7UBQM =D55O -----END PGP SIGNATURE----- --Apple-Mail=_E012EBF8-BAA7-4B92-BCE8-E4C098D47E92--