From mboxrd@z Thu Jan 1 00:00:00 1970 From: Fyodor Ustinov Subject: read vs write. Some tests. Date: Wed, 01 Jun 2011 17:58:14 +0300 Message-ID: <4DE65386.90209@ufm.su> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail.ufm.su ([77.120.103.19]:52033 "EHLO mail.ufm.su" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757985Ab1FAO6S (ORCPT ); Wed, 1 Jun 2011 10:58:18 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.ufm.su (Postfix) with ESMTP id 860E7600485 for ; Wed, 1 Jun 2011 17:58:15 +0300 (EEST) Received: from mail.ufm.su ([127.0.0.1]) by localhost (mail.ufm.su [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id LjsC8oQHsEq1 for ; Wed, 1 Jun 2011 17:58:15 +0300 (EEST) Received: from [192.168.2.22] (unknown [94.232.181.14]) by mail.ufm.su (Postfix) with ESMTPSA id 5BAFB600484 for ; Wed, 1 Jun 2011 17:58:15 +0300 (EEST) Sender: ceph-devel-owner@vger.kernel.org List-ID: To: ceph-devel@vger.kernel.org ceph - 0.28.2 from repository client - linux 2.6.39/64 All osd servers have 4G RAM. Journal on 1G tempfs. 2*1G ethernet (etherchannel) client server have 2G RAM. 2*1G ethernet (etherchannel) In tests used "dd if=/dev/zero of=file bs=8M count=3000" for write and "dd if=file of=/dev/null bs=8M count=3000" for read. For rbd instead "file" used "/dev/rbd0". In "ceph fs" additionaly used "iozone -a -y 8M -i 0 -i 1 -i 2 -n25g -g25g" Tests results: kernel ceph fs: dd write: 149.748 s, 168 MB/s dd read: 451.835 s, 55.7 MB/s iozone write: 165 MB/s iozone rewrite: 165 MB/s iozone randow write: 165 MB/s iozone read: 53 MB/s iozone reread: 55 MB/s iozone random read: 41 MB/s rbd: dd wite: 212.583 s, 118 MB/s dd read: 480.374 s, 52.4 MB/s Frankly I do not quite understand what was happening. WBR, Fyodor.