From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Priebe Subject: Re: OSD Hardware questions Date: Wed, 27 Jun 2012 17:13:20 +0200 Message-ID: <4FEB2310.9080801@profihost.ag> References: <4FEB04CC.4050008@profihost.ag> <4FEB10DA.7010206@inktank.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail.profihost.ag ([85.158.179.208]:58138 "EHLO mail.profihost.ag" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756584Ab2F0PNW (ORCPT ); Wed, 27 Jun 2012 11:13:22 -0400 In-Reply-To: <4FEB10DA.7010206@inktank.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Mark Nelson Cc: "ceph-devel@vger.kernel.org" Hi Mark, > Am 27.06.2012 15:55, schrieb Mark Nelson: > On 6/27/12 8:04 AM, Stefan Priebe - Profihost AG wrote: > Hi Stefan, > > I'm not entirely clear how you are coming to the conclusion regarding > the CPU requirements. If we go by the "1Ghz per OSD" suggestion, does > that mean you plan to have 3.6GHz*20/1GHz = 72 OSDs per server? oh i'm sorry it seems you got me wrong. I've a testsetup 4x OSDs with one disk each in ONE Server with a Intel Xeon 3,6Ghz. Each of the 4 ceph-osd processes take up to 170% CPU usage right now. So with these 4 osd disks and daemons i go up to 800% load. So EACH osd process takes up to 2 cores of 3,6 Ghz. So i need right now 2 Core of 3,6Ghz each per OSD drive. So if i want to use 8-10 drives per osd server i need 20 cores of 3,6Ghz. Anything wrong? Greets Stefan