From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josh Durgin Subject: Re: how to debug slow rbd block device Date: Wed, 23 May 2012 00:33:54 -0700 Message-ID: <4FBC92E2.5020807@inktank.com> References: <4FBB8A5B.9010500@profihost.ag> <4FBBEBC8.1000205@profihost.ag> <1C70F3FB753C4AEC97247E04FAE3C733@inktank.com> <4FBBF74C.9020608@profihost.ag> <45F1742481D84E7A90951816DB23609F@inktank.com> <4FBBFE7B.4060406@profihost.ag> <65E9589544C4489F93761035433ADC01@inktank.com> <4FBC811F.5060004@profihost.ag> <4FBC83F3.7070400@inktank.com> <4FBC8B41.1020300@profihost.ag> <4FBC8F8F.6060004@inktank.com> <4FBC904A.7090407@profihost.ag> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pz0-f46.google.com ([209.85.210.46]:61221 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753723Ab2EWHd4 (ORCPT ); Wed, 23 May 2012 03:33:56 -0400 Received: by dady13 with SMTP id y13so9362803dad.19 for ; Wed, 23 May 2012 00:33:56 -0700 (PDT) In-Reply-To: <4FBC904A.7090407@profihost.ag> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Stefan Priebe - Profihost AG Cc: Greg Farnum , ceph-devel@vger.kernel.org On 05/23/2012 12:22 AM, Stefan Priebe - Profihost AG wrote: > Am 23.05.2012 09:19, schrieb Josh Durgin: >> On 05/23/2012 12:01 AM, Stefan Priebe - Profihost AG wrote: >> You can use any of the rbd-specific options (like rbd_cache_max_dirty) >> with qemu>= 0.15. >> >> You can set them in a global ceph.conf file, or specify them on the qemu >> command line like: >> >> qemu -m 512 -drive >> file=rbd:pool/image:rbd_cache_max_dirty=0:rbd_cache=true,format=raw,if=virtio > ah thanks and sorry. Is there a way to verify which options are active / > working on a specific rbd block device? There's no way to ask which options it's using while it's running. That would probably be a good thing to add (maybe as an admin socket command). Until then, if you want to know the exact settings of all your rbd disks, you can specify all the necessary options on the qemu command line, and not have a ceph.conf file. Josh