From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Kirkwood Subject: Re: Ceph RBD performance - random writes Date: Thu, 09 Aug 2012 15:54:35 +1200 Message-ID: <5023347B.6060806@catalyst.net.nz> References: <5021F6D1.7000004@catalyst.net.nz> <5022B3F4.5050109@inktank.com> <5022E121.4070004@inktank.com> <5022F7EF.2020007@catalyst.net.nz> <50230797.8040008@catalyst.net.nz> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from bertrand.catalyst.net.nz ([202.78.240.40]:39686 "EHLO mail.catalyst.net.nz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751396Ab2HIDyh (ORCPT ); Wed, 8 Aug 2012 23:54:37 -0400 In-Reply-To: <50230797.8040008@catalyst.net.nz> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Mark Nelson Cc: Josh Durgin , ceph-devel@vger.kernel.org On 09/08/12 12:43, Mark Kirkwood wrote: > >> > > > I tried out a raft of xfs config changes and also made the Ceph > journal really big (10G): > > $ mkfs.xfs -f -l internal,size=1024m -d agcount=4 /dev/sd[b,c]2 > > + mount options with nobarrier,logbufs=8 > > The results improved a little, but still very slow for small request > sizes... Some more careful analysis showed that all the benefit derived from the ceph storage reinit after the filesystem was remade, so going back gradually to the default filesystem options (mkfs.xfs, default mount with noatime, discard) and 2G journal results in the same numbers as I posted with the tweaked settings. So sorry, appears to be nothing gained (on this system anyway) from said tweaking. Regards Mark