[Beowulf] Slection from processor choices; Requesting Giudence

[Douglas Eadline]

>
> Several persons replied and not a SINGLE ONE of them talks about
> one way pingpong latency, which is one of the most important features
> of a highend network for *many* applications.

Sigh, as I mentioned in my past post, go to the link below
Understand that it requires reading skills.

  http://www.clustermonkey.net//content/view/121/33/1/1/

Look at Table One and the two graphs, there are numbers there.
Read the numbers. They are MPI single byte latency for NetPipe.

GigE is not perfect. My point is that for many applications
it can work well. There are many other applications
that need better networking. It is a price to performance
argument.

BTW, the NICs I used in the link above were $35 Intel MT/1000
desktop (32 bit PCI) cards. I managed to get 14.6 HPL GFLOPS
and 4.35 GROMACS GFLOPS out of 8 nodes consisting of hardware
with a total costs of $2500. (much less using today prices)
Background is at the following link:

 http://www.clustermonkey.net//content/view/41/33/

As a point of reference, a quad opteron 270 (2GHz) reported
4.31 GROMACS GFLOPS.


-- 
Doug