From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267866AbUG3WyV (ORCPT ); Fri, 30 Jul 2004 18:54:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267867AbUG3WyU (ORCPT ); Fri, 30 Jul 2004 18:54:20 -0400 Received: from viper.oldcity.dca.net ([216.158.38.4]:31413 "HELO viper.oldcity.dca.net") by vger.kernel.org with SMTP id S267866AbUG3WyR (ORCPT ); Fri, 30 Jul 2004 18:54:17 -0400 Subject: Re: [patch] voluntary-preempt-2.6.8-rc2-M5 From: Lee Revell To: Ingo Molnar Cc: linux-kernel , Andrew Morton , Scott Wood In-Reply-To: <20040730064431.GA17777@elte.hu> References: <1090732537.738.2.camel@mindpipe> <1090795742.719.4.camel@mindpipe> <20040726082330.GA22764@elte.hu> <1090830574.6936.96.camel@mindpipe> <20040726083537.GA24948@elte.hu> <1090832436.6936.105.camel@mindpipe> <20040726124059.GA14005@elte.hu> <20040726204720.GA26561@elte.hu> <20040729222657.GA10449@elte.hu> <1091141622.30033.3.camel@mindpipe> <20040730064431.GA17777@elte.hu> Content-Type: text/plain Message-Id: <1091228074.805.6.camel@mindpipe> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Fri, 30 Jul 2004 18:54:39 -0400 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2004-07-30 at 02:44, Ingo Molnar wrote: > * Lee Revell wrote: > > > After running jackd with L2 all night, the only repeated XRUN was this > > one: > > > > ALSA /home/rlrevell/cvs/alsa/alsa-driver/alsa-kernel/core/pcm_lib.c:139: XRUN: pcmC0D2c > > [] dump_stack+0x17/0x20 > > [] snd_pcm_period_elapsed+0x27b/0x3e0 [snd_pcm] > > [] snd_emu10k1_interrupt+0xd1/0x3c0 [snd_emu10k1] > > [] handle_IRQ_event+0x47/0x90 > > [] do_IRQ+0xe3/0x1b0 > > [] common_interrupt+0x18/0x20 > > [] add_to_swap+0x21/0xc0 > > [] shrink_list+0x156/0x4b0 > > [] shrink_cache+0x14d/0x370 > > [] shrink_zone+0xa8/0xf0 > > [] balance_pgdat+0x1be/0x220 > > [] kswapd+0xa9/0xb0 > > [] kernel_thread_helper+0x5/0x10 > > > > This produced a few ~2ms XRUNs. The shrink_zone -> shrink_cache -> > > shrink_list is a recurring motif. > > > > Is this addressed in M2? > > not yet. I havent seen this latency yet, nor are there any immediately > clear clues in the xrun logs you sent. (it would still be nice to check > out -M2, to see whether with all those configurability changes it > matches the latencies of L2+your-irq.c-hack.) I discovered that a few of the XRUN traces were spurious - jackd apparently does something while stopping and starting that produces an XRUN trace but that jackd does not consider an error. I will fix this in jackd. The msync() related XRUN triggered by apt-get is definitely real. Here are my results with 2.6.8-rc2-mm1-M5. max usecs All IRQs threaded 349 Soundcard IRQ not threaded 227 Soundcard IRQ not threaded + max_sectors_kb -> 64 119 I will test next with 2.6.8-rc2-M5. Lee