From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick - South Valley Internet Subject: Creating a Load Balanced E-mail Server with NFS mounts with CentOS - how to optimize for performance? Date: Fri, 13 Jul 2007 16:51:38 -0700 Message-ID: <4698100A.1070702@garlic.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" To: nfs@lists.sourceforge.net Return-path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.92] helo=mail.sourceforge.net) by sc8-sf-list2-new.sourceforge.net with esmtp (Exim 4.43) id 1I9UvB-0004Ur-VB for nfs@lists.sourceforge.net; Fri, 13 Jul 2007 16:51:40 -0700 Received: from sequoia.garlic.com ([216.139.0.84]) by mail.sourceforge.net with esmtp (Exim 4.44) id 1I9UvE-0007pS-HH for nfs@lists.sourceforge.net; Fri, 13 Jul 2007 16:51:41 -0700 Received: from [216.139.11.36] (unknown [216.139.11.36]) by sequoia.garlic.com (Postfix) with ESMTP id 0184B3668 for ; Fri, 13 Jul 2007 16:51:39 -0700 (PDT) List-Id: "Discussion of NFS under Linux development, interoperability, and testing." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: nfs-bounces@lists.sourceforge.net Errors-To: nfs-bounces@lists.sourceforge.net Hi all, I'm finishing up our new load balanced e-mail server which consists of two Dell dual cpu Opterons NFS mounting our 1.6TB RAID 5 server - all 3 machines run CentOS. I have VMWare server installed on both Dell Opterons which both machines run a CentOS LDAP server (uses 256mb RAM), and a CentOS Postfix server. I have noticed no performance loss running VMWare, as far as I can tell. The reason I mention this is because I've had experience in the past with other applications, such as Trixbox/Asterisk that require you to NOT run this on a VM due to issues with real time processing and such. Just want to make sure that this isn't the case for this scenerio (which I don't think, since I'm only experiencing issues on the NFS mounted directories) Anyhow, I can successfully mount the NFS from both Postfix VM's without a problem. I created a /vol/vol0/home directory on the NFS, and mount that to /home on both Postfix VM's. Doing a 'ls -l' in /home takes forever, sometimes longer than I wish (30+ seconds, sometimes longer). I read the NFS performance documentation on testing the read and write speeds and timing them, and I've come up with these: ##################### [root@somebox mnt]# time dd if=/dev/zero of=/home/testfile bs=16k count=16384 16384+0 records in 16384+0 records out real 0m43.282s user 0m0.010s sys 0m2.043s [root@somebox mnt]# time dd if=/home/testfile of=/dev/null bs=16k 16384+0 records in 16384+0 records out real 0m22.943s user 0m0.016s sys 0m0.629s #################### I've tried to set different rsize and wsize (4096, 8192, 16384, and 32768), and it doesn't seem to be doing any different. I've checked the switch settings to make sure there weren't any inconsistencies and are set to 100xFD. My /etc/fstab looks like this: xxx.yyy.com:/vol/vol0/home /home nfs rw,hard,intr,rsize=32768,wsize=32768 0 0 xxx.yyy.com:/vol/vol0/spool-mail /spool-mail nfs rw,hard,intr,rsize=32768,wsize=32768 0 0 xxx.yyy.com:/vol/vol0/spool-xxx-mqueue /spool-mqueue nfs rw,hard,intr,rsize=32768,wsize=32768 0 0 I'm concerned because there will be a lot of activity on these servers, and I need this to be as fast as possible. Do I have my mountpoints defined properly? If I need to provide hardware descriptions of my machines, let me know and I will do a lspci. Thanks to everyone in advance. Patrick ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs