From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Priebe - Profihost AG Subject: slow performance even when using SSDs Date: Thu, 10 May 2012 14:09:13 +0200 Message-ID: <4FABAFE9.5060202@profihost.ag> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Return-path: Received: from mail.profihost.ag ([85.158.179.208]:35379 "EHLO mail.profihost.ag" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756492Ab2EJMQG (ORCPT ); Thu, 10 May 2012 08:16:06 -0400 Sender: ceph-devel-owner@vger.kernel.org List-ID: To: ceph-devel@vger.kernel.org Dear List, i'm doing a testsetup with ceph v0.46 and wanted to know how fast ceph is. my testsetup: 3 servers with Intel Xeon X3440, 180GB SSD Intel 520 Series, 4GB RAM, 2x 1Gbit/s LAN each All 3 are running as mon a-c and osd 0-2. Two of them are also running as mds.2 and mds.3 (has 8GB RAM instead of 4GB). All machines run ceph v0.46 and vanilla Linux Kernel v3.0.30 and all of them use btrfs on the ssd which serves /srv/{osd,mon}.X. All of them use eth0+eth1 as bond0 (mode 6). This gives me: rados -p rbd bench 60 write ... Total time run: 61.465323 Total writes made: 776 Write size: 4194304 Bandwidth (MB/sec): 50.500 Average Latency: 1.2654 Max latency: 2.77124 Min latency: 0.170936 Shouldn't it be at least 100MB/s? (1Gbit/s / 8) And rados -p rbd bench 60 write -b 4096 gives pretty bad results: Total time run: 60.221130 Total writes made: 6401 Write size: 4096 Bandwidth (MB/sec): 0.415 Average Latency: 0.150525 Max latency: 1.12647 Min latency: 0.026599 All btrfs ssds are also mounted with noatime. Thanks for your help! Greets Stefan