From mboxrd@z Thu Jan 1 00:00:00 1970 From: George Shuklin Subject: Ceph write performance Date: Fri, 20 Jul 2012 14:24:15 +0400 Message-ID: <500931CF.9040407@selectel.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-lb0-f174.google.com ([209.85.217.174]:63942 "EHLO mail-lb0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751490Ab2GTKYT (ORCPT ); Fri, 20 Jul 2012 06:24:19 -0400 Received: by mail-lb0-f174.google.com with SMTP id gm6so4820033lbb.19 for ; Fri, 20 Jul 2012 03:24:18 -0700 (PDT) Sender: ceph-devel-owner@vger.kernel.org List-ID: To: ceph-devel@vger.kernel.org Good day. I've start to play with Ceph... And I found some kinda strange performance issues. I'm not sure if this is due ceph limitation or my bad setup. Setup: osd - xfs on ramdisk (only one osd) mds - raid0 on 10 disks mon - second raid0 on 10 disks I've mount ceph share at localhost and run FIO (randwrite, 4k, iodepth=32) What I've got: 1900 IOPS on writing (4k block, 1Gb span). Normally fio shows about 200kIOPS writing on ramdisk. Why it was so slow? I've done setup exactly like described here: http://ceph.com/docs/master/start/quick-start/#start-the-ceph-cluster (but one osd). Thanks.