From owner-freebsd-isp@FreeBSD.ORG Tue Apr 18 11:40:41 2006 Return-Path: X-Original-To: freebsd-isp@freebsd.org Delivered-To: freebsd-isp@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2370B16A409 for ; Tue, 18 Apr 2006 11:40:41 +0000 (UTC) (envelope-from anderson@centtech.com) Received: from mh2.centtech.com (moat3.centtech.com [207.200.51.50]) by mx1.FreeBSD.org (Postfix) with ESMTP id E544843D6E for ; Tue, 18 Apr 2006 11:40:39 +0000 (GMT) (envelope-from anderson@centtech.com) Received: from [10.177.171.220] (neutrino.centtech.com [10.177.171.220]) by mh2.centtech.com (8.13.1/8.13.1) with ESMTP id k3IBea8K089308; Tue, 18 Apr 2006 06:40:36 -0500 (CDT) (envelope-from anderson@centtech.com) Message-ID: <4444D029.8060109@centtech.com> Date: Tue, 18 Apr 2006 06:40:25 -0500 From: Eric Anderson User-Agent: Thunderbird 1.5 (X11/20060402) MIME-Version: 1.0 To: David Gilbert References: <17475.43946.264571.52593@canoe.dclg.ca> <17475.54375.95109.55657@canoe.dclg.ca> In-Reply-To: <17475.54375.95109.55657@canoe.dclg.ca> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: ClamAV 0.87.1/1404/Tue Apr 18 05:03:40 2006 on mh2.centtech.com X-Virus-Status: Clean Cc: FreeBSD ISP , Francisco Reyes Subject: Re: NFS optimization X-BeenThere: freebsd-isp@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Internet Services Providers List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 18 Apr 2006 11:40:41 -0000 David Gilbert wrote: >>>>>> "Francisco" == Francisco Reyes writes: > > Francisco> What would be a good way to determine how many nfsd > Francisco> proccesses one should have? I erred in the side of caution > Francisco> since had to literally through an NFS setup into production > Francisco> without been able to do much testing. Set 35 processes. My > Francisco> busiest nfsd are: 250 hours 50 " 24 " 11 " 7 " 4 " 3 " 2 " > Francisco> 1 " > > Francisco> The rest are under 1 hour. Does that mean that I should be > Francisco> ok with 10 processes? > > Roughly, yes. You'll see NFSd's normally decline exponentially with > an inflection point. If your machine is completely dedicated to NFS, > you probably want to run lots. The overhead of extra NFSd processes > is fairly small. If you rarely do NFS, the default of 4 may even be > overkill. > > Consider that if you are "out" of nfsd's, the penalty is increased > latency for some small number of transactions that wait for an nfsd to > become available.. Even if you have tonnes of NFSd processes, if disk > is a limiting factor, more nfsd's won't speed the process. I have found that having too little can easily cause clients to block on nfs under peak usage times, so I tend to bump the number way up. There's little to no harm in it. > Something that most peoople don't consider is that the number of NFSd > process can balance the concurrency of NFS clients against local disk > requirements. If, say, you run a busy database on the NFS server, you > may want run fewer NFSd process to increase the disk bandwidth > resources available to the database. > > Francisco> To kill the least active ones, I just "kill" them? or is > Francisco> there a better way to restart the whole nfs server side? > > I rarely 'kill' an nfsd. Always thought that was bad. Killing any > nfsd is equivalent. If you kill one that is further up the queue, the > ones later in the queue move up (AFAIK). Still... I always change the > boot parameters and leave the processes currently running when I tune > the number of nfsd's. I usually look at my nfsd's, and see what the distribution of run time is on them. I like to see at minimum a few (maybe 5% or so) with 0:00.00 runtime - which (to me) means that I had enough to service the queue, and a few extra that were bored. For my setup, this means typically between 256 and 512 nfsd's (with one server at 1024). Eric -- ------------------------------------------------------------------------ Eric Anderson Sr. Systems Administrator Centaur Technology Anything that works is better than anything that doesn't. ------------------------------------------------------------------------