[comp.parallel] solving ode's and pde's on heterogenous mixtures of machines

annala%neuro.usc.edu@usc.edu (A J Annala) (09/04/89)

I am beginning to study possible solutions to the problem of solving
large systems of differential equations (linear & nonlinear ode's &
pde's) as part of an effort to use computer modeling as an aid for
understanding how biological neural networks (e.g. the cerebellum)
operate.  Several people have attempted to analyze possible means to
accelerate such computations by using either vector supercomputers
or various regular interconnected homogeneous processor arrays.

In my case, I have a large collection of machines available for use
in my simulation work including Aliant, Convex, Cray, DEC, Gould,
Pyramid, Silicon Graphics, and Sun systems.  I have available means
for automatically starting up servers, handling remote procedure
calls, transferring data (integers, floating point numbers, etc)
between machines in a common format, and coordinating assignment of
tasks from a central dispatcher task running on my own workstation.
So far, I have only used this assembly of machines for ray tracing.
However, I want to use this large computing capacity to do rapid
computations for my modeling work.

The problem, however, is that I have found no literature references
on building models using pde's and/or ode's with portions of the
computations being performed with varying degrees of precision on
a heterogenous mixture of machines.  Perhaps someone has already
thought this problem through.  Or perhaps I could interest one of
the readers of this newsgroup to write up their thoughts on solving
this problem.  In any case, a simple solution taking into account
use of the native floating point format and computing structure of
individual processors with sharing of information among processors
in a standard format would enable one to tap into the vast unused
capacity of workstations spread throughout most campuses and across
the country.  In my case, the ability to make effective use of the
local workstations (of which there are hundreds with Motorola 68020
and 68881 chips as well as high speed risc etc) may outperform the
available capacity of our local supercomputer center.

Any advice you would have to offer on corrdinating many different
machines in a single modeling experiment would be much appreciated.
Please send email resposes to:  "annala%neuro.usc.edu@usc.edu"

Thanks, AJ Annala, USC Neuroscience Program