From owner-freebsd-performance@FreeBSD.ORG Sat Jan 24 18:17:03 2004 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 81AF816A4CE; Sat, 24 Jan 2004 18:17:03 -0800 (PST) Received: from fledge.watson.org (fledge.watson.org [204.156.12.50]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8B02443D1F; Sat, 24 Jan 2004 18:17:01 -0800 (PST) (envelope-from robert@fledge.watson.org) Received: from fledge.watson.org (localhost [127.0.0.1]) by fledge.watson.org (8.12.10/8.12.10) with ESMTP id i0P2EqUd069682; Sat, 24 Jan 2004 21:14:52 -0500 (EST) (envelope-from robert@fledge.watson.org) Received: from localhost (robert@localhost)i0P2EptA069679; Sat, 24 Jan 2004 21:14:52 -0500 (EST) (envelope-from robert@fledge.watson.org) Date: Sat, 24 Jan 2004 21:14:51 -0500 (EST) From: Robert Watson X-Sender: robert@fledge.watson.org To: Willem Jan Withagen In-Reply-To: <003c01c3de8d$d569edb0$471b3dd4@dual> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: performance@FreeBSD.ORG cc: current@FreeBSD.ORG Subject: Re: Old SUN NFS performance papers. X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 25 Jan 2004 02:17:03 -0000 On Mon, 19 Jan 2004, Willem Jan Withagen wrote: > I had no responses to my recent question on the difference between NFS > over UDP and TCP. So perhaps nobody cares?? > > So I tried searching but have not found much yet. Does anybody know > where to find the white papers SUN once wrote about tuning NFS??? They > should be at sun, but where?? All other suggestions to read are > welcomed as well. > > Given my last posting I'm building two machines to do some NFS benchmark > testing on. Suggestions on what people "always wanted to know (tm)" are > also welcom, and I'll see if I can get them integrated. I've found the > benchmarks in /usr/ports, some might do so nice work as well. > > If people are interested I'll keep them posted in performance@ --WjW I haven't done much benchmarking on NFS lately, but something worth remembering is that people have spent a lot of time researching and optimizing TCP for a variety of connection types, whereas the NFS code basically has a static implementation of RPC backoff and flow control that hasn't evolved much. TCP is aware of things like the pathwise-mtu to the server and adapts, whereas UDP just loses packets due to fragmentation, especially if you are using larger block sizes. Please do post your discoveries on performance@, and perhaps we could build an NFS performance tuning section in the FreeBSD Handbook (or if there's not that much content, add it to the FAQ)? Robert N M Watson FreeBSD Core Team, TrustedBSD Projects robert@fledge.watson.org Senior Research Scientist, McAfee Research