Separate HTML for Basic Foil 30 Examples of Collective Communication/Computation

Basic HTML version of Foils prepared 10 Oct 1995

Foil 30 Examples of Collective Communication/Computation

From Fox Presentation Fall 1995 CPS615 Basic Simulation Track for Computational Science -- Fall Semester 95. by Geoffrey C. Fox

Four Processors where each has a send buffer of size 2

0 1 2 3 Processors

(2,4) (5,7) (0,3) (6,2) Initial Send Buffers

MPI_BCAST with root=2

(0,3) (0,3) (0,3) (0,3) Resultant Buffers

MPI_REDUCE with action MPI_MIN and root=0

(0,2) (_,_) (_,_) (_,_) Resultant Buffers

MPI_ALLREDUCE with action MPI_MIN and root=0

(0,2) (0,2) (0,2) (0,2) Resultant Buffers

MPI_REDUCE with action MPI_SUM and root=1

(_,_) (13,16) (_,_) (_,_) Resultant Buffers