Re: [SLUG] NFS and bandwidth

From: Derek Glidden (dglidden@illusionary.com)
Date: Wed May 08 2002 - 11:28:11 EDT


On Wed, 2002-05-08 at 09:02, Russell Hires wrote:
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> Hello everyone,
>
> I volunteer at a Weightman Middle School in Wesley Chapel and there's a
> computer lab full of iMacs (about 30). I've finally gotten Linux installed on
> one of them, and now I'm going to use the one as an NFS server for the others
> that I plan on booting into Linux as diskless workstations. But the Tech
> coordinator voiced some trepidation about this as it relates to bandwidth,
> because even though there is a ton of Macs in that school, bandwidth still is
> ridiculously small. So, my question is: how much bandwidth does NFS use? How
> much will it affect the network? Are there any other questions I should be
> asking? Any suggestions?

NFS is not known for its network efficiency, but it's certainly less
chatty than Appletalk (MacOS) or SMB (Windows) for filesharing, which
both rely on lots of broadcast traffic to figure out what's on the
network with them.

Asking "how much bandwidth" for a network filesharing protocol is kind
of a non-question, though since it's going to be dependent on the size
file you're transferring, how many people are utilizing the NFS server,
etc. Obviously, if one person is reading one small file over the
network, it'll be fast. If twenty people are trying to read very large
files over the same network, it'll be slower. It's not going to be
significantly different from anything else they might be using there
overall since you're still just moving files around the network and the
whole question is more related to the size of the files than anything
else.

I'd recommend, if possible, putting a 100Mbps card in the server if
that's all you can get away with. That would at least allow the server
to serve up, theoretically, ten different 10Mbps clients before hitting
its own bandwidth limitations. On a 100Mbps network, of course. If the
whole network is only 10Mbps, then never mind...

> The reason for all of this is the GIMP. Photoshop licenses aren't cheap!
> There's an art professor that comes in to the school to teach some of the
> more artistically gifted students every so often. I don't know his schedule,
> though, which means I haven't been able to show him this free software yet.
> So I figure this is a great use for Linux! :-D

I think once you show it off, and explain the fact that's it's all free
software, any complaints about network performance will be
overridden... :)

-- 
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