Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752742AbYHLSRz (ORCPT ); Tue, 12 Aug 2008 14:17:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751052AbYHLSRs (ORCPT ); Tue, 12 Aug 2008 14:17:48 -0400 Received: from e28smtp02.in.ibm.com ([59.145.155.2]:53494 "EHLO e28esmtp02.in.ibm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750808AbYHLSRr (ORCPT ); Tue, 12 Aug 2008 14:17:47 -0400 Date: Tue, 12 Aug 2008 23:47:35 +0530 From: "Aneesh Kumar K.V" To: Randy Dunlap Cc: lkml Subject: Re: INFO: task blocked for more than 120 seconds Message-ID: <20080812181735.GA6476@skywalker> References: <20080811112712.f858d77c.randy.dunlap@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080811112712.f858d77c.randy.dunlap@oracle.com> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3212 Lines: 71 On Mon, Aug 11, 2008 at 11:27:12AM -0700, Randy Dunlap wrote: > On 2.6.27-rc2-git4 and several previous kernels, I see several > of these messages. E.g.: > > INFO: task kjournald:665 blocked for more than 120 seconds. > INFO: task stress:17797 blocked for more than 120 seconds. > INFO: task stress:17805 blocked for more than 120 seconds. > > > Has anyone tracked this down? Should I attempt to bisect it? > (on x86_64, SMP, 8 GB RAM) > > > > INFO: task kjournald:665 blocked for more than 120 seconds. > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > kjournald D ffff88027e04be30 4592 665 2 > ffff88027e04bdd0 0000000000000046 ffff88027e04bd90 ffffffff8022b5f8 > ffff88027e703090 ffff880178c91bc0 ffff88027e7033d0 0000000178c91c08 > ffff88027e04bdb0 ffff88027e04be30 ffff88017eaf80f0 0000000000000246 > Call Trace: > [] ? __wake_up_common+0x41/0x74 > [] journal_commit_transaction+0xe9/0xd7e > [] ? lock_timer_base+0x26/0x4a > [] ? autoremove_wake_function+0x0/0x38 > [] ? try_to_del_timer_sync+0x56/0x62 > [] kjournald+0xc3/0x1fb > [] ? autoremove_wake_function+0x0/0x38 > [] ? kjournald+0x0/0x1fb > [] kthread+0x49/0x76 > [] child_rip+0xa/0x11 > [] ? kthread+0x0/0x76 > [] ? child_rip+0x0/0x11 > > INFO: task stress:17797 blocked for more than 120 seconds. > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > stress D ffff88017eaf8024 5088 17797 17795 > ffff8801f4055cd8 0000000000000082 0000000000000086 ffff88027e04bec0 > ffff880178c93090 ffff88017faf75f0 ffff880178c933d0 0000000300000001 > 0000000000000292 ffff8801f4055ce8 ffff88017eaf80a8 0000000000000246 > Call Trace: > [] log_wait_commit+0xa4/0xf4 > [] ? autoremove_wake_function+0x0/0x38 > [] journal_stop+0x17c/0x1a9 > [] journal_force_commit+0x23/0x25 > [] ext3_force_commit+0x26/0x28 > [] ext3_write_inode+0x39/0x3f > [] __writeback_single_inode+0x180/0x284 > [] ? wake_bit_function+0x0/0x2a > [] generic_sync_sb_inodes+0x1c3/0x29e > [] sync_sb_inodes+0x9/0xb > [] sync_inodes_sb+0x95/0x9c > [] __sync_inodes+0x62/0xaf > [] sync_inodes+0x2e/0x33 > [] do_sync+0x34/0x59 > [] sys_sync+0xe/0x13 > [] system_call_fastpath+0x16/0x1b > Committing a transaction would means writing rest of the meta-data in the transaction. And that would imply forcing most of the buffer_heads to disk in ordered mode. This can result a lot of seeks and make take more thatn 120 seconds. -aneesh -- 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/