[Fwd: Re: 32-port gigabit switch]

[Dave Vehrs]

On Thu, 2003-03-06 at 16:10, Mark Hahn wrote:
> it's very beowulfish to take advantage of changing hardware.  
> many/most server boards these days have two builtin gigabit links.  
> and why not take advantage of the new crop of small/cheap gige switches?
> pricewatch has 8-ports for $US 320!

I hadn't seen that, but lets use that as a working number...so $40 a
port, and I'll even assume that it scales to 16 port switches too.  

Now you wanted to run 16 switches so $10240 in switches.  Or $160 per
node for 64 nodes. Just for the switches.

> > Plus the additional admin time to
> > configure and maintain all the networking options.  
> 
> wiring requires some patience and care; I don't really see why admin
> would be hard.  in fact, I think for the grid-of-switches approach, the 
> builtin spanning tree would work fine, since there are no redundant links,
> unlike with a fat tree.  you'd still have to set routes on each node,
> but wouldn't that just take a pretty simple perl script?

Wiring fiber on Myrinet takes time too.  You're right this could be a
push.  Some good for one side, some for the other too.

Now I've never setup a grid-of-switches, what would the routing tables
look like?  It doesn't seem like that simple a perl script to me, but
maybe I'm missing something.

> I don't see myrinet (or quadrics or IB) at <$100/port any time soon.

Given that your solution was $160 per node for just the switches, maybe
$200/port is a better comparison.

Dave


-- 
David E Vehrs, System Engineer		Aspen Systems
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