SnRad on Cplant
SnRad on Cplant
This performance data is for running a radiation transport solver on
an unstructured grid. A 3-d EXODUS mesh is constructed, then
partitioned with Chaco and NEMESIS. A direct solution to the
Bolztmann equation for radiation flux is formulated by sweeping across
the grid in each of many ordinate directions simultaneously. The
communication required during the solve involves many tiny messages
being sent asynchronously to neighboring processors. Thus it is a
good test of communication capabilities on CPlant.
Solutions were computed for three different grid sizes on varying
numbers of processors. For each simulation 80 ordinate directions (Sn
= 8) were computed using 2 energy groups.
A CPlant DEC-Alpha processor runs this radiation solver about 2x
faster than the Intel Pentium 333 Mhz processors used in the Tflops
machine. The cross-over point in performance between the two machines
is at about 64-128 processors for grids of these sizes.
