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Parallel I/O

High Performance Fortran is primarily designed to obtain high performance on massively parallel computers. Such massively parallel machines also need massively parallel I/O.

There are difficulties in getting high performance I/O:

In particular Fortran file organization has limits:

With these in mind there are two major approaches that have been suggested:

  1. Define hints (annotations) that do not change file semantics, in the spirit of data distribution. (This gives some information to the compiler.)
  2. Introduce parallel read/write operations that are not necessarily compatible with sequential ones.
Thu May 5 15:11:02 CDT 1994