From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Priebe - Profihost AG Subject: Re: poor OSD performance using kernel 3.4 Date: Fri, 25 May 2012 13:31:15 +0200 Message-ID: <4FBF6D83.20907@profihost.ag> References: <4FBE415E.8030702@profihost.ag> <4FBE7ABC.5020502@profihost.ag> <4FBE838D.4000303@inktank.com> <4FBE8662.1070801@profihost.ag> <4FBEE5FF.7080907@inktank.com> <4FBF407C.70407@profihost.ag> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mail.profihost.ag ([85.158.179.208]:57142 "EHLO mail.profihost.ag" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755546Ab2EYLa7 (ORCPT ); Fri, 25 May 2012 07:30:59 -0400 In-Reply-To: <4FBF407C.70407@profihost.ag> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Mark Nelson Cc: "ceph-devel@vger.kernel.org" Some speed tests with different Kernel Versions. The same applies to other FS like btrfs. I used "rados -p data bench 100 write -t 16" for all tests and a freshly created FS. mount options were always: noatime,nodiratime,nobarrier. 3.0.30 with XFS speed is always between 120 and 160MB/s Total time run: 100.510061 Total writes made: 3605 Write size: 4194304 Bandwidth (MB/sec): 143.468 Average Latency: 0.445714 Max latency: 1.99929 Min latency: 0.084812 3.2.18 with XFS speed is between 40 and 170MB/s Total time run: 100.795653 Total writes made: 3384 Write size: 4194304 Bandwidth (MB/sec): 134.292 Average Latency: 0.476297 Max latency: 2.92075 Min latency: 0.084884 3.3.7 with XFS !! speed heavily jumps between 0 and 170 MB/s !! Total time run: 107.398166 Total writes made: 2455 Write size: 4194304 Bandwidth (MB/sec): 91.435 Average Latency: 0.699819 Max latency: 13.8117 Min latency: 0.084624 3.4 with XFS !! speed heavily jumps between 0 and 130 MB/s - most if the time it's near 0 !! Total time run: 115.433531 Total writes made: 468 Write size: 4194304 Bandwidth (MB/sec): 16.217 Average Latency: 3.9452 Max latency: 53.4356 Min latency: 0.091276 Stefan