From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f170.google.com ([209.85.192.170]:57649 "EHLO mail-pd0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753439Ab3JUPBo (ORCPT ); Mon, 21 Oct 2013 11:01:44 -0400 Received: by mail-pd0-f170.google.com with SMTP id v10so2412955pde.1 for ; Mon, 21 Oct 2013 08:01:44 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20131021123728.GJ1032@twin.jikos.cz> References: <20131021123728.GJ1032@twin.jikos.cz> From: david pu Date: Mon, 21 Oct 2013 23:01:14 +0800 Message-ID: Subject: Re: task btrfs-transacti:1076 blocked for more than 120 seconds To: dsterba@suse.cz, david pu , linux-btrfs@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Mon, Oct 21, 2013 at 8:37 PM, David Sterba wrote: > On Mon, Oct 21, 2013 at 04:36:41PM +0800, david pu wrote: >> I'm running into btrfs-transaction hang issue with below call trace >> from dmesg[1]. >> when this issue happens, all filesystem r/w access will be blocked and >> no response in terminal. I'm using Ubuntu raring(linux 3.2 kernel) >> 64bit kernel as below: >> Linux dpu-e6410 3.2.0-36-generic #57-Ubuntu SMP Tue Jan 8 21:44:52 UTC >> 2013 x86_64 x86_64 x86_64 GNU/Linux >> >> is it a known issue? How to recover from such task hung status? > > The message can occur when > > 1) system is under heavy load or fragmentation slows down the IO, this > is harmless, the warnings stop after a few cycles It happens after I login into Ubuntu with lightdm.I did not find a method to reproduce it consistently. > > 2) it's a bug and the system cannot move forward due to a deadlock, the > warnings appear repeatedly and the IO seems to be stalled > > For a 3.2 kernel it's possible that the bug is there. I'm very sorry about the kernel version I pasted in previous email. I pasted wrong uname -a result. it should be: Linux dpu-desktop 3.8.0-31-generic #46-Ubuntu SMP Tue Sep 10 20:03:44 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux will upgrade kernel to latest version to have a try. > > david -- () ASCII Ribbon Campaign /\ Keep it simple!