Interpolation from coarse grid to fine periodic

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: rations computation Lines of Code 800 566 600 More important than the size difference 400that it is is easier to write, read, modify, and maintain 202 200 0 F+MPI 87 95 70 242 77 ZPL A-ZPL Language NAS MG Linecounts 1200 comm/sync/dir declarations computation 1000 800 600 400 200 0 MPI Java HPF OpenMP Serial A-ZPL NAS MG Speedup: ZPL vs. Fortran + MPI ZPL scales better than MPI since its communication is expressed in an implementation-neutral way; this permits the compiler to use SHMEM on this Cray T3E but MPI on a commodity cluster ZPL also performs better at smaller scales where communication is not the bottleneck ⇒ new languages need not imply performance sacrifices Similar observations—and more dramatic ones—have been made using more recent architectures, languages, and benchmarks Cray T3E Generality Notes Each ZPL binary supports: •  an arbitrary load-time problem size •  an arbitrary load-time # of processors •  1D/2D/3D data decompositions This MPI binary only supports: •  a static 2**k problem size •  a static 2**j # of processors •  a 3D data decomposition The code could be rewritten to relax these assumptions, but at what cost? - in performance? - in development effort? Cray T3E Global-view models can benefit Productivity 1200 communication 1000 declarations Lines of Code 800 computation 566 600 400 202 200 242 87 70 95 77 F+MPI ZPL A-ZPL 0 Language Cray T3E •  more programmable, flexible •  able to achieve competitive perfor...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online