From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Nelson Subject: Re: OSD Hardware questions Date: Wed, 27 Jun 2012 11:00:07 -0500 Message-ID: <4FEB2E07.6010402@inktank.com> References: <4FEB04CC.4050008@profihost.ag> <4FEB10DA.7010206@inktank.com> <4FEB2310.9080801@profihost.ag> <4FEB26A7.4070507@profihost.ag> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-qc0-f170.google.com ([209.85.216.170]:32891 "EHLO mail-qc0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757860Ab2F0QAZ (ORCPT ); Wed, 27 Jun 2012 12:00:25 -0400 Received: by qcmt36 with SMTP id t36so841447qcm.1 for ; Wed, 27 Jun 2012 09:00:25 -0700 (PDT) In-Reply-To: <4FEB26A7.4070507@profihost.ag> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Stefan Priebe Cc: Gregory Farnum , "ceph-devel@vger.kernel.org" On 06/27/2012 10:28 AM, Stefan Priebe wrote: > > Am 27.06.2012 17:21, schrieb Gregory Farnum: >> >> >> Well, as we said, 1GHz/OSD was a WAG (wild-ass guess), but 3.6GHz+/OSD >> is farther outside of that range than I would have expected. It might >> just be a consequence of using SSDs, since they can sustain so much more >> throughput. > > Sure it was just so much away from 1Ghz that i wanted to ask. > >> What is the cluster doing when you see those CPU usage numbers? > random write I/O from one KVM. 14k I/Ops with random 4k writes. > > Stefan I think I was seeing about 80-85% CPU utilization with 5 SSD OSDs on our 6-core AMD nodes, but I was just doing sequential writes with rados bench. Mark