From owner-freebsd-questions@FreeBSD.ORG Wed Jan 14 19:32:54 2004 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6ABFE16A4CE for ; Wed, 14 Jan 2004 19:32:54 -0800 (PST) Received: from mail.seekingfire.com (coyote.seekingfire.com [24.72.10.212]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2573643D48 for ; Wed, 14 Jan 2004 19:32:51 -0800 (PST) (envelope-from tillman@seekingfire.com) Received: by mail.seekingfire.com (Postfix, from userid 500) id 1C9B7BF; Wed, 14 Jan 2004 21:32:50 -0600 (CST) Date: Wed, 14 Jan 2004 21:32:49 -0600 From: Tillman Hodgson To: FreeBSD-Questions Message-ID: <20040115033249.GI415@seekingfire.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="vKcNkqnJHUUp475E" Content-Disposition: inline X-Habeas-SWE-1: winter into spring X-Habeas-SWE-2: brightly anticipated X-Habeas-SWE-3: like Habeas SWE (tm) X-Habeas-SWE-4: Copyright 2002 Habeas (tm) X-Habeas-SWE-5: Sender Warranted Email (SWE) (tm). The sender of this X-Habeas-SWE-6: email in exchange for a license for this Habeas X-Habeas-SWE-7: warrant mark warrants that this is a Habeas Compliant X-Habeas-SWE-8: Message (HCM) and not spam. Please report use of this X-Habeas-SWE-9: mark in spam to . X-GPG-Key-ID: 828AFC7B X-GPG-Fingerprint: 5584 14BA C9EB 1524 0E68 F543 0F0A 7FBC 828A FC7B X-GPG-Key: http://www.seekingfire.com/gpg_key.asc X-Urban-Legend: There is lots of hidden information in headers User-Agent: Mutt/1.5.5.1i Subject: make -jX build(world|kernel): test results X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 15 Jan 2004 03:32:54 -0000 --vKcNkqnJHUUp475E Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Howdy, Occasionally the question pops up on the questions@ list about what the fastest -jX number is for a single CPU system. I had some spare time so I tried out a small matrix of possibilities. My conclusion is that using -jX at all is mostly a waste of time on single CPU systems running -STABLE (even with multiple spindles being involved), especially when one considers that -jX may introduce build problems. NOTES: * I used the simple shell "time" command * /usr/obj was cleaned out before each run and I waited at least 30 seconds afterwards for write caching to settle down * This is my regular build host for my network * I built 4 kernels: 3 customized and GENERIC (see above for why) * Celeron 900, 256Mb of RAM, /usr/src and /usr/obj are both on their own set of spindles * /usr/obj consumes part of a vinum mirror on dual 40Gb 7200RPM Maxtor 6L040J2's (the remaining vinum filesystems weren't active during this test) * /usr/src is on a 2,1Gb Compaq ST32550N SCSI-2 drive * The operating system is on separate spindles RESULTS: buildworld -j2 buildworld -j3 buildworld -j4 buildworld =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D real 57m10.367s 54m10.992s 55m7.494s 55m1.459s user 38m5.436s 38m20.852s 38m22.453s 38m23.056s sys 9m2.801s 10m12.876s 10m17.140s 10m14.792s buildkernel -j2 buildkernel -j3 buildkernel -j4 buildkernel =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D real 36m59.994s 36m58.988s 37m42.956s 37m31.627s user 29m35.597s 29m43.405s 29m43.846s 29m48.652s sys 4m50.478s 5m26.372s 5m26.883s 5m22.763s Thought this might be of some interest, -T --=20 Re: alt.sysadmin.recovery A fitting punishment for kindly naivete, to end up belonging here.=20 - A.S.R. quote (Chris Johnson) --vKcNkqnJHUUp475E Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (FreeBSD) iD8DBQFABgnhDwp/vIKK/HsRAod4AKCxMrNmXRiOJ/4IobXoi0vTSWKr+wCg0Szz D3/dPObFEq3lWA/+gD/BjxY= =tHOl -----END PGP SIGNATURE----- --vKcNkqnJHUUp475E--