From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josh Durgin Subject: Re: Latest bobtail branch still crashing KVM VMs in bh_write_commit() Date: Wed, 20 Mar 2013 13:32:57 -0700 Message-ID: <514A1CF9.5040807@inktank.com> References: <514A13A8.7010002@profihost.ag> <514A189E.7070802@profihost.ag> <514A19D7.1040309@inktank.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pb0-f45.google.com ([209.85.160.45]:61658 "EHLO mail-pb0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752702Ab3CTUj0 (ORCPT ); Wed, 20 Mar 2013 16:39:26 -0400 Received: by mail-pb0-f45.google.com with SMTP id ro8so1661448pbb.4 for ; Wed, 20 Mar 2013 13:39:25 -0700 (PDT) In-Reply-To: <514A19D7.1040309@inktank.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Stefan Priebe Cc: Travis Rhoden , bcampbell@axcess-financial.com, ceph-devel On 03/20/2013 01:19 PM, Josh Durgin wrote: > On 03/20/2013 01:14 PM, Stefan Priebe wrote: >> Hi, >> >>> In this case, they are format 2. And they are from cloned snapshots. >>> Exactly like the following: >>> >>> # rbd ls -l -p volumes >>> NAME SIZE >>> PARENT FMT PROT LOCK >>> volume-099a6d74-05bd-4f00-a12e-009d60629aa8 5120M >>> images/b8bdda90-664b-4906-86d6-dd33735441f2@snap 2 >>> >>> I'm doing an OpenStack boot-from-volume setup. >> >> OK i've never used cloned snapshots so maybe this is the reason. >> >>>> strange i've never seen this. Which qemu version? >>> >>> # qemu-x86_64 -version >>> qemu-x86_64 version 1.0 (qemu-kvm-1.0), Copyright (c) 2003-2008 >>> Fabrice Bellard >>> >>> that's coming from Ubuntu 12.04 apt repos. >> >> maybe you should try qemu 1.4 there are a LOT of bugfixes. qemu-kvm does >> not exist anymore it was merged into qemu with 1.3 or 1.4. > > This particular problem won't be solved by upgrading qemu. It's a ceph > bug. Disabling caching would work around the issue. > > Travis, could you get a log from qemu of this happening with: > > debug ms = 20 > debug objectcacher = 20 > debug rbd = 20 > log file = /path/writeable/by/qemu If it doesn't reproduce with those settings, try changing debug ms to 1 instead of 20. > From those we can tell whether the issue is on the client side at least, > and hopefully what's causing it. > > Thanks! > Josh