weekly status report

[Julian C. Cummings]

Hi All,

My Pooma hours have been few and far between
the past few weeks, and that will continue 
until June 1st, when my class is finished and
we have had our Caltech ASCI Research Review.

I did manage to spend a few hours today solving 
some problems with Particle Boundary Conditions
in Nolen's MC++ code kernel.  It is apparent 
that I need to fix the deferred destroy lists in
Particles so that they are actually sorted lists
of indices in ascending order.  I am thinking to
use STL map containers for this.

The next big thing to do is try to modify this 
MC++ kernel to use multiple patches and then run
with threads and/or MPI.  One thing Nolen and I 
are interested in is seeing if we can create Fields
that are replicated across contexts rather than
being distributed.  We'd like to emulate what MCNP
does with distributing particles evenly across 
processors and storing the whole Field on every
processor.  If I understand things correctly, the 
present version of RemoteEngine will not do this 
for us, because it operates under the assumption 
that if the data is remote, there must be a 
corresponding RemoteEngine on some other processor 
that has the data locally.  But I think we can just
declare a single-patch Field in each context and
achieve the desired effect.  The only tricky part is
how to do global reductions of this Field across 
contexts.  Helpful ideas would be appreciated!

Thanks, Julian C.


Dr. Julian C. Cummings
Staff Scientist, CACR/Caltech
(626) 395-2543
cummings at cacr.caltech.edu