From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263165AbTDGBNC (for ); Sun, 6 Apr 2003 21:13:02 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263176AbTDGBNC (for ); Sun, 6 Apr 2003 21:13:02 -0400 Received: from [12.47.58.55] ([12.47.58.55]:22228 "EHLO pao-ex01.pao.digeo.com") by vger.kernel.org with ESMTP id S263165AbTDGBNA (for ); Sun, 6 Apr 2003 21:13:00 -0400 Date: Sun, 6 Apr 2003 18:24:35 -0700 From: Andrew Morton To: Zwane Mwaikambo Cc: linux-kernel@vger.kernel.org, mingo@elte.hu, Linus Torvalds Subject: Re: 2.5.66-(bk) == horrible response times for non X11 applications Message-Id: <20030406182435.5a243297.akpm@digeo.com> In-Reply-To: References: X-Mailer: Sylpheed version 0.8.9 (GTK+ 1.2.10; i586-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 07 Apr 2003 01:24:29.0930 (UTC) FILETIME=[6FBD2CA0:01C2FCA4] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Zwane Mwaikambo wrote: > > This was not reproduceable with 2.4.18-3 nor with 2.5.66 and the > following patch applied; > > http://www.kernel.org/pub/linux/kernel/people/akpm/patches/2.5/2.5.66/2.5.66-mm3/broken-out/sched-interactivity-backboost-revert.patch > There have been multiple reports of this patch fixing starvation problems. We need to either apply it or fix up the problem by other means. From: Ingo Molnar the patch below fixes George's setiathome problems (as expected). It essentially turns off Linus' improvement, but i dont think it can be fixed sanely. the problem with setiathome is that it displays something every now and then - so it gets a backboost from X, and hovers at a relatively high priority. kernel/sched.c | 13 +------------ 1 files changed, 1 insertion(+), 12 deletions(-) diff -puN kernel/sched.c~sched-interactivity-backboost-revert kernel/sched.c --- 25/kernel/sched.c~sched-interactivity-backboost-revert 2003-03-28 22:30:08.000000000 -0800 +++ 25-akpm/kernel/sched.c 2003-03-28 22:30:08.000000000 -0800 @@ -379,19 +379,8 @@ static inline int activate_task(task_t * * boosting tasks that are related to maximum-interactive * tasks. */ - if (sleep_avg > MAX_SLEEP_AVG) { - if (!in_interrupt()) { - sleep_avg += current->sleep_avg - MAX_SLEEP_AVG; - if (sleep_avg > MAX_SLEEP_AVG) - sleep_avg = MAX_SLEEP_AVG; - - if (current->sleep_avg != sleep_avg) { - current->sleep_avg = sleep_avg; - requeue_waker = 1; - } - } + if (sleep_avg > MAX_SLEEP_AVG) sleep_avg = MAX_SLEEP_AVG; - } if (p->sleep_avg != sleep_avg) { p->sleep_avg = sleep_avg; p->prio = effective_prio(p); _