From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262063AbTEUM7T (ORCPT ); Wed, 21 May 2003 08:59:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262023AbTEUM7T (ORCPT ); Wed, 21 May 2003 08:59:19 -0400 Received: from node-d-1ea6.a2000.nl ([62.195.30.166]:63983 "EHLO laptop.fenrus.com") by vger.kernel.org with ESMTP id S262063AbTEUM7S (ORCPT ); Wed, 21 May 2003 08:59:18 -0400 Subject: Re: [Linux-ia64] Re: web page on O(1) scheduler From: Arjan van de Ven Reply-To: arjanv@redhat.com To: Duraid Madina Cc: linux-kernel@vger.kernel.org In-Reply-To: <3ECB57A4.1010804@octopus.com.au> References: <16075.8557.309002.866895@napali.hpl.hp.com> <1053507692.1301.1.camel@laptop.fenrus.com> <3ECB57A4.1010804@octopus.com.au> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-wqNv0fddgTcRxZIjZUQF" Organization: Red Hat, Inc. Message-Id: <1053522732.1301.4.camel@laptop.fenrus.com> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.4 (1.2.4-2) Date: 21 May 2003 15:12:12 +0200 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --=-wqNv0fddgTcRxZIjZUQF Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Wed, 2003-05-21 at 12:40, Duraid Madina wrote: > Dear Arjan, >=20 >=20 > /////// > // O > // > This is a graduate > / \__ ~ student, laboratory > || ///// assistant, automotive > (\ \) (~) // o <--- engineer or other > ( \ \ / / // > unfortunate soul > ( \ \/ / ____________/ \__O attempting to get > ( \__/ / ___ ______\// performance out of a > / | /@ ( / / ______)/ machine running Linux > ( |// \ \ / / (_) by writing a simple > \ () \ \O/ and correct > \ | ) ) multithreaded program. > ) ) / / > ( |_ / /_ > (____> (____> >=20 > ^ > | > | > | > | >=20 > This is you. >=20 >=20 if you had spent the time you spent on this colorful graphic on reading SUS or Posix about what sched_yield() means, you would actually have learned something. sched_yield() means "I'm the least important thing in the system". It's the wrong thing for cross-cpu spinlocks; futexes are optimal for that. For letting higher priority tasks run a sleep(0) is also far more closer to the right behavior than a sched_yield(). --=-wqNv0fddgTcRxZIjZUQF Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.2 (GNU/Linux) iD8DBQA+y3ssxULwo51rQBIRAgyKAJ9n0t2mBSmeUqrzxyzIldiEUJCZAQCfec2z Y03qbLDK8Y8rOoU7/dV+sLo= =ugqy -----END PGP SIGNATURE----- --=-wqNv0fddgTcRxZIjZUQF--