The Concept of HPF

HPF is a set of extensions to the Fortran 90 language. Fortran 90 considered a better platform than C or C++.

HPF targets the Data Parallel programming paradigm which allows systems of interconnected processors to be easily programmed,

• each processor runs same program -- the Single Program Multiple Data (SPMD) model,
• each processor operates on part of the overall data,
• HPF directives say which processor gets what data,
• Fortran 90 and HPF statements define parallelism,

It brings parallel programming to the masses!

It has been said that explicit message-passing programs are to HPF as assembler programs are to high level languages. The analogy runs quite well as HPF programs are simple to write but will never quite achieve the efficiency of an explicit message-passing equivalent.

The HPF directives specify the location (or layout) of the data and the parallel array syntax, intrinsic functions, HPF library calls and HPF FORALL or INDEPENDENT DO loops specify the parallelism.

A Fortran 90 program can be passed unaltered through an HPF compiler and will be parallelised using the system defaults. This will not be the most effective way to parallelise code but it in many cases will give a significant increase in speed.

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