From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267361AbUGNKpj (ORCPT ); Wed, 14 Jul 2004 06:45:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267358AbUGNKpj (ORCPT ); Wed, 14 Jul 2004 06:45:39 -0400 Received: from cantor.suse.de ([195.135.220.2]:31898 "EHLO Cantor.suse.de") by vger.kernel.org with ESMTP id S267361AbUGNKpW (ORCPT ); Wed, 14 Jul 2004 06:45:22 -0400 Date: Wed, 14 Jul 2004 12:43:37 +0200 Message-ID: From: Takashi Iwai To: Andrew Morton Cc: Lee Revell , linux-kernel@vger.kernel.org Subject: Re: Ext3 vs. ReiserFS results (was Re: XRUN traces) In-Reply-To: <20040713175833.6ab037ef.akpm@osdl.org> References: <1089758294.2747.4.camel@mindpipe> <20040713161004.37a4654e.akpm@osdl.org> <1089763038.3392.8.camel@mindpipe> <20040713175833.6ab037ef.akpm@osdl.org> User-Agent: Wanderlust/2.10.1 (Watching The Wheels) SEMI/1.14.5 (Awara-Onsen) FLIM/1.14.5 (Demachiyanagi) APEL/10.6 MULE XEmacs/21.4 (patch 15) (Security Through Obscurity) (i386-suse-linux) MIME-Version: 1.0 (generated by SEMI 1.14.5 - "Awara-Onsen") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org At Tue, 13 Jul 2004 17:58:33 -0700, Andrew Morton wrote: > > Lee Revell wrote: > > > > Jul 13 19:51:45 mindpipe kernel: ALSA /usr/src/alsa-cvs-1.0.5/alsa-driver/alsa-kernel/core/pcm_lib.c:169: XRUN: pcmC0D0p > > Jul 13 19:51:45 mindpipe kernel: [dump_stack+23/32] dump_stack+0x17/0x20 > > Jul 13 19:51:45 mindpipe kernel: [__crc_totalram_pages+562733/3558647] snd_pcm_period_elapsed+0x2c7/0x400 [snd_pcm] > > Jul 13 19:51:45 mindpipe kernel: [__crc_totalram_pages+631725/3558647] snd_emu10k1_interrupt+0x377/0x400 [snd_emu10k1] > > Jul 13 19:51:45 mindpipe kernel: [handle_IRQ_event+51/96] handle_IRQ_event+0x33/0x60 > > Jul 13 19:51:45 mindpipe kernel: [do_IRQ+165/368] do_IRQ+0xa5/0x170 > > Jul 13 19:51:45 mindpipe kernel: [common_interrupt+24/32] common_interrupt+0x18/0x20 > > Jul 13 19:51:45 mindpipe kernel: [d_callback+29/64] d_callback+0x1d/0x40 > > Jul 13 19:51:45 mindpipe kernel: [rcu_do_batch+62/80] rcu_do_batch+0x3e/0x50 > > Jul 13 19:51:45 mindpipe kernel: [rcu_process_callbacks+150/256] rcu_process_callbacks+0x96/0x100 > > Jul 13 19:51:45 mindpipe kernel: [tasklet_action+68/112] tasklet_action+0x44/0x70 > > Jul 13 19:51:45 mindpipe kernel: [__do_softirq+131/144] __do_softirq+0x83/0x90 > > Jul 13 19:51:45 mindpipe kernel: [do_softirq+53/64] do_softirq+0x35/0x40 > > Jul 13 19:51:45 mindpipe kernel: [do_IRQ+277/368] do_IRQ+0x115/0x170 > > Jul 13 19:51:45 mindpipe kernel: [common_interrupt+24/32] common_interrupt+0x18/0x20 > > Jul 13 19:51:45 mindpipe kernel: [poll_freewait+46/80] poll_freewait+0x2e/0x50 > > Jul 13 19:51:45 mindpipe kernel: [sys_poll+472/544] sys_poll+0x1d8/0x220 > > This one's going to be a problem. It's due to RCU freeing a large number > of dentries in one hit. The recent patches to daemonize softirq may help? There was a discussion on LKML (on March?) about the latency improvement of RCU. Rearming the tasklet fixed the latency problem indeed. Takashi