From owner-freebsd-scsi@FreeBSD.ORG Mon Feb 15 23:45:44 2010 Return-Path: Delivered-To: freebsd-scsi@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5E9171065697; Mon, 15 Feb 2010 23:45:44 +0000 (UTC) (envelope-from 000.fbsd@quip.cz) Received: from elsa.codelab.cz (elsa.codelab.cz [94.124.105.4]) by mx1.freebsd.org (Postfix) with ESMTP id 1E3BB8FC18; Mon, 15 Feb 2010 23:45:43 +0000 (UTC) Received: from elsa.codelab.cz (localhost.codelab.cz [127.0.0.1]) by elsa.codelab.cz (Postfix) with ESMTP id B6F2B19E023; Tue, 16 Feb 2010 00:45:41 +0100 (CET) Received: from [192.168.1.2] (r5bb235.net.upc.cz [86.49.61.235]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by elsa.codelab.cz (Postfix) with ESMTPSA id 6D03219E019; Tue, 16 Feb 2010 00:45:39 +0100 (CET) Message-ID: <4B79DCA2.1070005@quip.cz> Date: Tue, 16 Feb 2010 00:45:38 +0100 From: Miroslav Lachman <000.fbsd@quip.cz> User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9.1.7) Gecko/20100104 SeaMonkey/2.0.2 MIME-Version: 1.0 To: freebsd-scsi@freebsd.org References: 4B5F1553.4070709@quip.cz Content-Type: text/plain; charset=ISO-8859-2; format=flowed Content-Transfer-Encoding: 7bit Cc: ivoras@freebsd.org Subject: performance tuning of iSCSI and Dell MD3000i / gjournal problem X-BeenThere: freebsd-scsi@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SCSI subsystem List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 15 Feb 2010 23:45:44 -0000 I am sorry for my late reply, I am not subscribed to this list and I was busy by my other work. Please CC me next time. >> >> Just a note, I am still having performance problems with iSCSI and Dell >> MD3000i. >> I tried it with ZFS, but writing performance was even worse - about >> 3-5MB/s! Copying 33GB from local UFS partition do iSCSI ZFS partition >> takes almost 5 hours: > > You've written a lot of information here. Firstly, is your problem > related to iSCSI performance, ZFS performance or UFS performance? As it > looks to me, you are mostly complaining about iSCSI performance, right? I am complaining about iSCSI performance in general. I think it should give some better results on gigabit link with underlying RAID5 of 4 SATA 7200rpm drives. The performance is much below one physical SATA drive. Then I use 3 different setups to test if it is just iSCSI problem, or UFS+SU. UFS+SU have much lower write performance than UFS+Gjournal, but gjournal doesn't work well with iSCSI at boot time. And ZFS on iSCSI is the worst case with 5MB/s write performance! (I have much better experiences with ZFS on RAIDZ pool of 4 SATA drives) The mentioned iSCSI storage (Dell MD3000i) is now in production serving about 200Mbits (350Mbits in peaks) through Lighttpd, using UFS+SU. It is used almost read only, so write performance doesn't matter at this time, but if there will be any disaster and I will need to restore backups, it will take more than 2 days to copy 1TB of data! Miroslav Lachman