From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763619AbXKTUzX (ORCPT ); Tue, 20 Nov 2007 15:55:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756200AbXKTUzK (ORCPT ); Tue, 20 Nov 2007 15:55:10 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:47984 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752406AbXKTUzI (ORCPT ); Tue, 20 Nov 2007 15:55:08 -0500 Date: Tue, 20 Nov 2007 21:54:54 +0100 From: Ingo Molnar To: Pavel Machek Cc: kernel list , tglx@linutronix.de Subject: Re: nohz and strange sleep latencies Message-ID: <20071120205454.GD10008@elte.hu> References: <20071119203152.GA1772@elf.ucw.cz> <20071119205555.GA28696@elte.hu> <20071119211142.GA1857@elf.ucw.cz> <20071120085704.GA19950@elte.hu> <20071120105458.GA1597@elf.ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20071120105458.GA1597@elf.ucw.cz> User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.1.7-deb -1.5 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 * Pavel Machek wrote: > > and send us the output? (Enabling CONFIG_TIMER_STATS, > > CONFIG_SCHED_DEBUG and CONFIG_SCHEDSTATS would maximize the amount > > of information.) > > This was w/o hpet=disable . Do you want me to test with hpet=disable? no, this is fine. You've got a hpet clockevents driver and two lapic drivers: Clock Event Device: hpet set_next_event: hpet_legacy_next_event set_mode: hpet_legacy_set_mode event_handler: tick_handle_oneshot_broadcast Clock Event Device: lapic set_next_event: lapic_next_event set_mode: lapic_timer_setup event_handler: hrtimer_interrupt Clock Event Device: lapic set_next_event: lapic_next_event set_mode: lapic_timer_setup event_handler: hrtimer_interrupt to me this has the feeling of lapic breakage in C2 mode. Does it get any better if you boot with 'nolapic'? (but that might in turn turn off high-res timers and nohz in essence) Thomas, any ideas? Ingo