From owner-freebsd-performance@FreeBSD.ORG Wed Feb 20 21:20:54 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 82C0416A406 for ; Wed, 20 Feb 2008 21:20:54 +0000 (UTC) (envelope-from bright@elvis.mu.org) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.freebsd.org (Postfix) with ESMTP id 6B63113C458 for ; Wed, 20 Feb 2008 21:20:54 +0000 (UTC) (envelope-from bright@elvis.mu.org) Received: by elvis.mu.org (Postfix, from userid 1192) id BED5A1A4D7E; Wed, 20 Feb 2008 13:01:18 -0800 (PST) Date: Wed, 20 Feb 2008 13:01:18 -0800 From: Alfred Perlstein To: Chuck Swiger Message-ID: <20080220210118.GY99258@elvis.mu.org> References: <27dbfc8c0802190243y113d3059yd0c602850a4dbd6b@mail.gmail.com> <47BB33AD.1050005@FreeBSD.org> <27dbfc8c0802200323r13f69905l4940d0d5accd1eb1@mail.gmail.com> <9BCE1D41-EC1A-4FE6-8551-E725DBE5D3A8@mac.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9BCE1D41-EC1A-4FE6-8551-E725DBE5D3A8@mac.com> User-Agent: Mutt/1.4.2.3i 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 21:20:54 -0000 * Chuck Swiger [080220 10:35] wrote: > Hi-- > > On Feb 20, 2008, at 3:23 AM, Valerio Daelli wrote: > > 99904 total packets received > [ ... ] > > > > 61441 fragments received > > [ ... ] > > 34819 output datagrams fragmented > > 208914 fragments created > > 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. -Alfred