PGAS Programming with UPC and Fortran Coarrays

Performance (TFlop/s)12/19/2012HIMENO• HIMENO Halo-Swap benchmark• Uses Jacobi method to solve Poisson’s equation• Looked at a distributed implementation for GPUs• When distributed this gives a stencil computation and haloswapcommunication.• Used draft OpenMP GPU directives stencil computation• used MPI or coarrays for halo-swap between processes• Coarray code for halo-swap was simple and was bestperforming of the optimized versions• There is still scope to optimize the coarray version (reduceextra data copy)45HIMENO7Himeno Benchmark - XL configurationMPI/ACC OptCAF/ACC Opt65432100 32 64 96 128 160 192 224 256Number of nodes4623