Beowulf Questions

[Randall Jouett]

On Sat, 2003-01-04 at 12:19, Mark Hahn wrote:
> > Personally, I don't think so, especially if we consider the
> > fact that in the not-too-distant future, networking speeds
> > will be up to snuff with the various tasks at hand. With these
> 
> ah!  I think this is the central fallacy that drives grid enthusiasm.


Maybe so, but the fact still remains that there are
certain task out that will most definitely take
advantage of more nodes being available. Not only
that, but the application will most definitely not
care where the nodes are coming from. In this instance,
all that should really matter is "the more nodes the
better."


BTW, I still stand by my statement that networking
speeds will increase, and also that this increase
will add to overall computing productivity.


> there simply is no coming breakthrough that will make all networking
> fast, low-latency, cheap, ubiquitous and low-power.  and grid
> (in the grand sense) really does require *all* those properties.


Well, I agree, to some extent, but where I differ from you
is with the word "latency." As I just said, there are applications
that will take advantage of the availability of more nodes.
So you don't get your answer in 2.3 microseconds. In a lot
of instances, nobody will actually care, and in some programming
situations, it will be down right miraculous that you can even
get an answer in a day! :^)
 

> oh, you will certainly manage to do some very interesting things 
> with wimpier networking, but with major compromises.  I don't see
> people doing parallel weather sims over 803.11*-connected nodes 
> any time soon.


Agreed, but they could be around the corner. IMHO, speculation
in this area would as least be a productive use of ones time,
and it sure in the hell beats the crap out of watching TV :^).


> but seti at home-type applications (very losely coupled
> and coarse-grained) would be a fine way to keep my fridge's brain
> busy.

NOW we're in the same ballpark, Mark :^).

> on the other hand, a fridge will always be a tiny fraction
> of the compute power of a desktop, so is it worth it?  not to mention
> the fact that seti at fridge will jack up my monthly power bill...

I don't think you'd even notice the fluctuation in your power bill,
especially when you consider the current draw of the compressor :^).
Well, you'd probably notice it a bit, but also remember that we're
using a currently viable application for comparison here and that
there is no telling what some ultra-creative geek might dream up
in the future.
 
> ultrawideband is an interesting development for this kind of networking,
> perhaps also in the optical range.  anyone interested in this stuff should
> read Robert Forward and Vernor Vinge's books (FS novels).

I was thinking about using a setup like this above 300 GHz,
where the spectrum isn't monitored by the FCC, if I remember
correctly.

 
> ps: I don't mean grid stuff isn't worthwhile, or that we can't do 
> any of it until the perfect network arrives.  there's lots of great 
> work going on - p2p networking, java/jini/jxta, etc.  I just don't see
> it being relevant to the beowulf world very soon, or ever being as 
> grand as the starry-eyed gridophiliacs would like to predict...


I totally agree here, Mark. OTOH, with enough people focusing
their efforts in this arena, there is probably no telling what
some of these people will come up with. Also note that we're
really talking time and distance here, and something like
a billion cubed nanobots cranking on a problem, taking up
an inch of physical space, has to be something that we
should all consider. Sure, it won't happen any time soon,
but the ramifications will surely be mind boggling. Can you
imagine saying something like this to your nano-bot cluster:

"Bots...You see that chick on TV? Well, I want you to duplicate
her overall looks, but please increase her bust size by 4 inches,
and make her appear right there, nude, and with a sexy grin on
her face." :^) :^). Move over holodeck :^) :^) :^).

Randall
--
Randall Jouett
Amateur Radio: AB5NI