From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268609AbUHNLwd (ORCPT ); Sat, 14 Aug 2004 07:52:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266481AbUHNLwb (ORCPT ); Sat, 14 Aug 2004 07:52:31 -0400 Received: from mx1.elte.hu ([157.181.1.137]:65232 "EHLO mx1.elte.hu") by vger.kernel.org with ESMTP id S268641AbUHNLvV (ORCPT ); Sat, 14 Aug 2004 07:51:21 -0400 Date: Sat, 14 Aug 2004 13:51:39 +0200 From: Ingo Molnar To: James Courtier-Dutton Cc: linux-kernel@vger.kernel.org, Lee Revell , Felipe Alfaro Solana , Florian Schmidt Subject: Re: [patch] Latency Tracer, voluntary-preempt-2.6.8-rc4-O6 Message-ID: <20040814115139.GB9705@elte.hu> References: <20040726083537.GA24948@elte.hu> <1090832436.6936.105.camel@mindpipe> <20040726124059.GA14005@elte.hu> <20040726204720.GA26561@elte.hu> <20040729222657.GA10449@elte.hu> <20040801193043.GA20277@elte.hu> <20040809104649.GA13299@elte.hu> <20040810132654.GA28915@elte.hu> <20040812235116.GA27838@elte.hu> <411DF776.6090102@superbug.demon.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <411DF776.6090102@superbug.demon.co.uk> User-Agent: Mutt/1.4.1i X-ELTE-SpamVersion: MailScanner 4.31.6-itk1 (ELTE 1.2) SpamAssassin 2.63 ClamAV 0.73 X-ELTE-VirusStatus: clean X-ELTE-SpamCheck: no X-ELTE-SpamCheck-Details: score=-4.9, required 5.9, autolearn=not spam, BAYES_00 -4.90 X-ELTE-SpamLevel: X-ELTE-SpamScore: -4 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * James Courtier-Dutton wrote: > I have tested this for a day now, and I have noticed problems: > 1) > kernel syslog gets a record like this: > > (default.hotplug/1470): 121 us critical section violates 100 us > threshold. > and the /proc/latency_trace gets: > > preemption latency trace v1.0 > > ----------------------------- > > latency: 121 us, entries: 1032 (1032) > > process: default.hotplug/1470, uid: 0 > > nice: -10, policy: 0, rt_priority: 0 > > =======> > > 0.000ms (+0.000ms): page_address (kmap_high) > > 0.000ms (+0.000ms): page_slot (page_address) > > 0.000ms (+0.000ms): flush_all_zero_pkmaps (kmap_high) > > 0.000ms (+0.000ms): set_page_address (flush_all_zero_pkmaps) > Could the patch be adjusted to make the syslog and the > /proc/latency_trace produce the same output? We cannot include the full trace in the syslog - it's possibly thousands of lines long. > 2) > I suspect that there is a problem with reiserfs, but when I detect a > momentary hang in the system(mouse stops moving), no latency_trace appears. well, the mouse could stop moving for a number of reasons. It's handled via the X server and if the X server is preempted (for whatever reason) then the mouse pointer isnt updated. you could try to change the mouse IRQ to be non-threaded. Also, do you have kernel_preemption set to 1? It defaults to 0. Ingo