From owner-freebsd-fs@FreeBSD.ORG Wed Sep 15 08:07:41 2010 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 93DE9106566C for ; Wed, 15 Sep 2010 08:07:41 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from qmta03.emeryville.ca.mail.comcast.net (qmta03.emeryville.ca.mail.comcast.net [76.96.30.32]) by mx1.freebsd.org (Postfix) with ESMTP id 781FF8FC1E for ; Wed, 15 Sep 2010 08:07:41 +0000 (UTC) Received: from omta16.emeryville.ca.mail.comcast.net ([76.96.30.72]) by qmta03.emeryville.ca.mail.comcast.net with comcast id 6w6D1f0011ZMdJ4A3w7h1z; Wed, 15 Sep 2010 08:07:41 +0000 Received: from koitsu.dyndns.org ([98.248.41.155]) by omta16.emeryville.ca.mail.comcast.net with comcast id 6w7g1f0023LrwQ28cw7gr5; Wed, 15 Sep 2010 08:07:40 +0000 Received: by icarus.home.lan (Postfix, from userid 1000) id 13D4D9B423; Wed, 15 Sep 2010 01:07:40 -0700 (PDT) Date: Wed, 15 Sep 2010 01:07:40 -0700 From: Jeremy Chadwick To: Andriy Gapon Message-ID: <20100915080740.GA55725@icarus.home.lan> References: <20100908084855.GF2465@deviant.kiev.zoral.com.ua> <4C874F00.3050605@freebsd.org> <4C8D087B.5040404@freebsd.org> <03537796FAB54E02959E2D64FC83004F@multiplay.co.uk> <4C8D280F.3040803@freebsd.org> <3FBF66BF11AA4CBBA6124CA435A4A31B@multiplay.co.uk> <4C8E4212.30000@freebsd.org> <4C9078E0.2050402@freebsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4C9078E0.2050402@freebsd.org> User-Agent: Mutt/1.5.20 (2009-06-14) Cc: freebsd-fs@freebsd.org Subject: Re: zfs very poor performance compared to ufs due to lack of cache? X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 15 Sep 2010 08:07:41 -0000 On Wed, Sep 15, 2010 at 10:42:24AM +0300, Andriy Gapon wrote: > on 14/09/2010 20:30 Steven Hartland said the following: > > Going to run the following tests:- > > 1. run a live test with "sendfile off" in the nginx config > > 2. run a live test with "sendfile on" in the nginx config. > > > > During these tests I'm going to monitor the following every minute:- > > time, kstat.zfs.misc.arcstats.size, vm.stats.vm.v_pdwakeups, > > vm.stats.vm.v_cache_count, vm.stats.vm.v_inactive_count, > > vm.stats.vm.v_active_count, vm.stats.vm.v_wire_count, > > vm.stats.vm.v_free_count > > > > Anything else that should be monitored? > > > > Before each test the machine will be rebooted to try to ensure as direct a > > comparison > > as possible. > > > > Anything else that I should add / change before running said tests or should > > monitor? > > This sounds sufficiently good. > If you could arrange to draw the graphs of the data it would be terrific :) Please be aware the OP is using RRDTool to store the sample data, which means the values you see in the graphs are going to be averaged unless he's taken the time to use MIN/MAX/LAST on both the CF and the DS (there is a difference): > > Now monitoring these each minute to an rrd and text file and updated > > 8-STABLE ... What I'm trying to say: averaged data may not show you what you're looking for, depending on what that is. :-) -- | Jeremy Chadwick jdc@parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP: 4BD6C0CB |