Date: Sun, 25 Jan 2004 11:04:25 +0000 From: dom@happygiraffe.net (Dominic Mitchell) To: Robert Watson <rwatson@FreeBSD.ORG> Cc: current@FreeBSD.ORG Subject: Re: Old SUN NFS performance papers. Message-ID: <20040125110425.GA35789@ppe.happygiraffe.net> In-Reply-To: <Pine.NEB.3.96L.1040124210942.31483E-100000@fledge.watson.org> References: <003c01c3de8d$d569edb0$471b3dd4@dual> <Pine.NEB.3.96L.1040124210942.31483E-100000@fledge.watson.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sat, Jan 24, 2004 at 09:14:51PM -0500, Robert Watson wrote: > 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)? I'm just playing with this... The first thing to note (probably) is to check that you can ping your server with a similiar size packet to the one you're using. I realised that my network isn't as robust as I thought it was very quickly yesterday, when pinging my server with an 8k packet. I was seeing 70% packet loss. The default ping showed no problems at all. The reason I mention it is that I'd been playing with NFS tuning because I had been seeing lockups. But the fault really lies at a lower level than NFS, it appears. -Dom
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20040125110425.GA35789>