Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752821AbXJVLVz (ORCPT ); Mon, 22 Oct 2007 07:21:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751963AbXJVLVp (ORCPT ); Mon, 22 Oct 2007 07:21:45 -0400 Received: from smtp.ustc.edu.cn ([202.38.64.16]:45036 "HELO ustc.edu.cn" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with SMTP id S1751922AbXJVLVn (ORCPT ); Mon, 22 Oct 2007 07:21:43 -0400 Message-ID: <393051953.24752@ustc.edu.cn> X-EYOUMAIL-SMTPAUTH: wfg@mail.ustc.edu.cn Date: Mon, 22 Oct 2007 19:19:08 +0800 From: Fengguang Wu To: Maxim Levitsky Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, Fengguang Wu , Andrew Morton Subject: Re: 100% iowait on one of cpus in current -git Message-ID: <20071022111907.GA21640@mail.ustc.edu.cn> References: <200710220822.52370.maximlevitsky@gmail.com> <200710221240.24386.maximlevitsky@gmail.com> <393050530.03287@ustc.edu.cn> <200710221258.11384.maximlevitsky@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200710221258.11384.maximlevitsky@gmail.com> X-GPG-Fingerprint: 53D2 DDCE AB5C 8DC6 188B 1CB1 F766 DA34 8D8B 1C6D User-Agent: Mutt/1.5.16 (2007-06-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2393 Lines: 59 On Mon, Oct 22, 2007 at 12:58:11PM +0200, Maxim Levitsky wrote: > On Monday 22 October 2007 12:55:25 Fengguang Wu wrote: > > On Mon, Oct 22, 2007 at 12:40:24PM +0200, Maxim Levitsky wrote: > > > On Monday 22 October 2007 12:22:10 Peter Zijlstra wrote: > > > > > [ 673.365631] pdflush D c21bdecc 0 221 2 > > > > > [ 673.365635] c21bdee0 00000046 00000002 c21bdecc c21bdec4 00000000 c21b3000 00000002 > > > > > [ 673.365643] c0134892 c21b3164 c1e00200 00000001 c7109280 c21bdec0 c03ff849 c21bdef0 > > > > > [ 673.365650] 00052974 00000000 000000ff 00000000 00000000 00000000 c21bdef0 000529dc > > > > > [ 673.365657] Call Trace: > > > > > [ 673.365659] [] schedule_timeout+0x48/0xc0 > > > > > [ 673.365663] [] io_schedule_timeout+0x5e/0xb0 > > > > > [ 673.365667] [] congestion_wait+0x71/0x90 > > > > > [ 673.365671] [] wb_kupdate+0x9e/0xf0 > > > > > [ 673.365675] [] pdflush+0x102/0x1d0 > > > > > [ 673.365679] [] kthread+0x42/0x70 > > > > > [ 673.365683] [] kernel_thread_helper+0x7/0x18 > > > > > > > > > > > > > That looks more like the inode writeback patches from Wu than the per > > > > bdi dirty stuff. The later typically hangs in balance_dirty_pages(). > > > > > > > > > > > > > > > > > > Yes, you are right, > > > > > > both revisions 1f7d6668c29b1dfa307a44844f9bb38356fc989b and 3e26c149c358529b1605f8959341d34bc4b880a3 work fine > > > But I didn't pay attention that those are before f4a1c2bce002f683801bcdbbc9fd89804614fb6b. > > > So, back to the drawing board.... :-) > > > > > > Will test revision 2e6883bdf49abd0e7f0d9b6297fc3be7ebb2250b, just after writeback patches. > > > > Thank you. I'll try if I can reproduce it locally... > > > > Fengguang > > > > > > Bingo, > > Revision 2e6883bdf49abd0e7f0d9b6297fc3be7ebb2250b shows this bug. > > I will now bisect to find exact patch that caused this bug, This one is most relevant: 1f7decf6d9f06dac008b8d66935c0c3b18e564f9 writeback: introduce writeback_control.more_io to indicate more io Still compiling the kernel... Thank you, Fengguang - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/