Basic HTML version of Foils prepared 17 Sept 1996

Foil 41 The Two Basic Distributions in HPF

From New CPS615HPF and Fortran90 Discussion Sept 17 96 Basic Simulation Track for Computational Science CPS615 -- Fall Semester 96. by Geoffrey C. Fox, Tom Haupt


We used BLOCK in the Laplace equation example and so this is appropriate distribution for "local" or geometric type problems
CYCLIC is called scattered in our early work (or is a special case of scattered which is perhaps random distribution of objects on processors) is appropriate in cases where "load-balancing" is more important than locality
  • Simplest examples are matrix inversion and graphics rendering problems
  • In solving equations (we will do later) Ax=b , there is no "nearest neighbor" structure between rows and columns, but rather one eliminates rows and columns and cyclic distribution ensures work remains balanced
  • In calculating pixels, work depends on complexity of picture at that pixel and so best to distribute pixels cyclically (or randomly) to processors.



© on Tue Oct 7 1997