From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030308AbXDWBNm (ORCPT ); Sun, 22 Apr 2007 21:13:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030342AbXDWBNl (ORCPT ); Sun, 22 Apr 2007 21:13:41 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:35356 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030308AbXDWBNl (ORCPT ); Sun, 22 Apr 2007 21:13:41 -0400 Date: Mon, 23 Apr 2007 03:12:29 +0200 From: Ingo Molnar To: linux-kernel@vger.kernel.org Cc: Linus Torvalds , Andrew Morton , Con Kolivas , Nick Piggin , Mike Galbraith , Arjan van de Ven , Peter Williams , Thomas Gleixner , caglar@pardus.org.tr, Willy Tarreau , Gene Heskett , Mark Lord , Ulrich Drepper Subject: [patch] CFS scheduler, -v5 Message-ID: <20070423011229.GA20367@elte.hu> References: <20070420140457.GA14017@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070420140457.GA14017@elte.hu> User-Agent: Mutt/1.4.2.2i X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.0.3 -2.0 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org i'm pleased to announce release -v5 of the CFS scheduler patchset. The patch against v2.6.21-rc7 and v2.6.20.7 can be downloaded from: http://redhat.com/~mingo/cfs-scheduler/ this CFS release mainly fixes regressions and improves interactivity: 13 files changed, 211 insertions(+), 199 deletions(-) the biggest user-visible change in -v5 are various interactivity improvements (especially under higher load) to fix reported regressions, and an improved way of handling nice levels. There's also a new sys_sched_yield_to() syscall implementation for i686 and x86_64. All known regressions have been fixed. (knock on wood) [ Note: while CFS's default preemption granularity is currently set to 5 msecs, this value does not directly transform into timeslices: for example two CPU-intense tasks will have effective timeslices of 10 msecs with this setting. ] Changes since -v4: - interactivity bugfix: fix xterm latencies and general desktop delays and child task startup delays under load. (reported by Willy Tarreau and Caglar Onur) - bugfix: the in_atomic_preempt_off() call on !PREEMPT_BKL was buggy and spammed the console with bogus warnings. - implementation fix: make the nice levels implementation starvation-free and smpnice-friendly. Remove the nice_offset hack. - feature: add initial sys_sched_yield_to() implementation. Not hooked into the futex code yet, but testers are encouraged to give the syscalls a try, on i686 the new syscall is __NR_yield_to==320, on x86_64 it's __NR_yield_to==280. The prototype is sys_sched_yield_to(pid_t), as suggested by Ulrich Drepper. - usability feature: add CONFIG_RENICE_X: those who dont want the kernel to renice X should disable this option. (the boot option and the sysctl is still available too) - removed my home-made "Con was right about scheduling fairness" attribution to Con's scheduler interactivity work - some have suggested that Con might want to see another text there. Con, please feel free to fill it in! - feature: make the CPU usage of nice levels logarithmic instead of linear. This is more usable and more intuitive. (Going four nice levels forward/backwards give half/twice the CPU power) [ This was requested a number of times in the past few years and is straightforward under CFS because there nice levels are not tied to any timeslice distribution mechanism. ] - cleanup: removed the stupid "Ingo was here" banner printk from sched_init(), the -cfs EXTRAVERSION serves the purpose (of identifying a booted up kernel as a CFS one) equally well. - various other code cleanups As usual, any sort of feedback, bugreport, fix and suggestion is more than welcome, Ingo