From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tim Small Subject: Re: Deadlock in md barrier code? / RAID1 / LVM CoW snapshot + ext3 / Debian 5.0 - lenny 2.6.26 kernel Date: Tue, 21 Sep 2010 22:02:25 +0100 Message-ID: <4C991D61.1040400@seoss.co.uk> References: <4C938103.1010304@seoss.co.uk> <20100918085925.5fee83ee@notabene> <4C97BD21.1040405@seoss.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4C97BD21.1040405@seoss.co.uk> Sender: linux-raid-owner@vger.kernel.org To: Neil Brown Cc: "linux-raid@vger.kernel.org" List-Id: linux-raid.ids Tim Small wrote: > http://buttersideup.com/files/md-raid1-lockup-lvm-snapshot/iodeadlock-sysrq-t.txt > > ... this was soon after the io to md2 stopped - md0 seems fine... > > oldshoreham:~# cat /proc/mdstat > Personalities : [raid1] > md2 : active raid1 sda6[0] sdb6[1] > 404600128 blocks [2/2] [UU] > [>....................] resync = 0.1% (437056/404600128) > finish=343321.2min speed=19K/sec > > > ... I also tried an older Debian 5.0.x kernel from Mar 2009, which is a > less-patched 2.6.26, and got the same results. 2.6.32 hasn't deadlocked > after 10 minutes (2.6.26 usually does within a minute of boot-up), so > I'll leave it re-syncing overnight... > 2.6.32 resynced to completion, but if possible I'd really like to get 2.6.26 running on this box, as it uses openvz, and the 2.6.32 openvz patches are still pretty green, I think. Is their anything in the sysrq-t output in that link of any use? Are there any patches I should try, or would it be better to start bisecting between 2.6.26 and 2.6.32 (assuming I can reproduce the problem without the load pattern which openvz is producing - which I probably can). Cheers, Tim. -- South East Open Source Solutions Limited Registered in England and Wales with company number 06134732. Registered Office: 2 Powell Gardens, Redhill, Surrey, RH1 1TQ VAT number: 900 6633 53 http://seoss.co.uk/ +44-(0)1273-808309