🚀 go-pugleaf

In article <uh311ae.675674229@sunmanager> uh311ae@sunmanager.lrz-muenchen.de (Henrik Klagges) writes:

>				:
>Basically, 4 bidirectionals isn't bad. I would prefer the 8 ones of the
>new transputers, especially given the fact that they support a virtual
>channel concept - i.e., giving you as many software channels as you want.
>The XX, YY only restriction, however, is severe and sounds like an engi-
>neering joke.
>				:

iWARP supports 20 logical communication channels which
are implemented in hardware by multiplexing 4 bidirectional
hardware busses. With these logical channels it is possible
to emulate for instance a 2^6 Hypercube on an 8x8 iWARP system
without introducing software overhead.

>		:
>At $9K half-Sparc performance ? I'd rather buy a full Sparc (including
>color monitor, 16Megs & HDD). For large parallelism, there is still a
>connection machine (SIMD), a BBN Butterfly, a Meiko Computing Surface,
>		:

The CM is an SIMD machine and the BBN a shared memory parallel
processor with the associated drawbacks. A competetive
Computing Surface either uses the i860 with the compiler problems
you mentioned, or an H1 (=T9000) which has not been officially
released yet (how about an optimizing H1 C compiler ?)

>		:
>The iWARP was from the very beginning designed to be a building block
>for 2D-mesh dataflow computers.
>		:

A dataflow computer (see for instance "Monsoon: ..." by Papadopoulos
and Culler in ISCA 90) is designed to execute efficiently dataflow
graphs typically expressed in a functional language (for instance ID).
iWARP is programmed in C or W2 using low latency communication
primitives. Standart numerical applications (SOR, dense linear algebra,
signal processing, ...) can be parallelized efficiently provided enough
local memory.  Although the current C compiler release does not support
LIW optimization, iWARP has a good communication speed / local
computation performance ratio compared to other distributed memory
parallel processors (MIMD) commerically available at the moment.

---------

Roland Ruehl				uucp:  uunet!mcsun!ethz!ruehl
Tel: (01) 256 5146 (Switzerland)	eunet: ruehl@iis.ethz.ch
     +411 256 5146 (International)

Integrated Systems Laboratory
ETH-Zentrum
8092 Zurich