From owner-freebsd-performance@FreeBSD.ORG Wed Feb 20 21:30:14 2008 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id EE28B16A402; Wed, 20 Feb 2008 21:30:14 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from mail-out4.apple.com (mail-out4.apple.com [17.254.13.23]) by mx1.freebsd.org (Postfix) with ESMTP id C2A1E13C45E; Wed, 20 Feb 2008 21:30:14 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from relay11.apple.com (relay11.apple.com [17.128.113.48]) by mail-out4.apple.com (Postfix) with ESMTP id C0C3722CFD76; Wed, 20 Feb 2008 13:30:14 -0800 (PST) Received: from relay11.apple.com (unknown [127.0.0.1]) by relay11.apple.com (Symantec Mail Security) with ESMTP id AB8D228091; Wed, 20 Feb 2008 13:30:14 -0800 (PST) X-AuditID: 11807130-a7c41bb0000028a7-b4-47bc9be6ac6e Received: from cswiger1.apple.com (cswiger1.apple.com [17.214.13.96]) by relay11.apple.com (Apple SCV relay) with ESMTP id 8D2902809C; Wed, 20 Feb 2008 13:30:14 -0800 (PST) Message-Id: From: Chuck Swiger To: Alfred Perlstein In-Reply-To: <20080220210118.GY99258@elvis.mu.org> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (Apple Message framework v919.2) Date: Wed, 20 Feb 2008 13:30:13 -0800 References: <27dbfc8c0802190243y113d3059yd0c602850a4dbd6b@mail.gmail.com> <47BB33AD.1050005@FreeBSD.org> <27dbfc8c0802200323r13f69905l4940d0d5accd1eb1@mail.gmail.com> <9BCE1D41-EC1A-4FE6-8551-E725DBE5D3A8@mac.com> <20080220210118.GY99258@elvis.mu.org> X-Mailer: Apple Mail (2.919.2) X-Brightmail-Tracker: AAAAAA== Cc: "freebsd-performance@freebsd.org" , Valerio Daelli Subject: Re: Bad performance of 7.0 nfs client with Solaris nfs server X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 20 Feb 2008 21:30:15 -0000 On Feb 20, 2008, at 1:01 PM, Alfred Perlstein wrote: >> Take a look at the level of packet fragmentation you are >> encountering; >> yes, this is expected and things will work but there is extra latency >> added when the IP stack has to reassemble packets before the data can >> be delivered. Try setting the NFS rsize/wsize to 1024 or perhaps >> 1400 >> and see whether that improves performance. >> >> Or, if your switch and NICs support it, see whether you can get Gb >> Ethernet jumbo frames working so that you don't have to fragment for >> 2K or 4K data packets.... > > TCP mounts do not have this problem. You can safely use > 32k or higher sizes with TCP without fragmentation. Oh, sure. But there is a bit more overhead with TCP transport than UDP-- for local (switched) networks, UDP generally seems to be a win...TCP seems to be a better choice over a VPN or some similar kind of WAN. -- -Chuck