Concurrent File Operations in a High Performance FORTRAN

Distributed memory multiprocessor systems can provide the computing power necessary for large-scale scientific applications. A critical performance issue for a number of these applications is the efficient transfer of data to secondary storage. Recently several research groups have proposed FORTRAN language extensions for exploiting the data parallelism of such scientific codes on distributed memory architectures. However, few of these high performance FORTRANs provide appropriate constructs for controlling the use of the parallel I/O capabilities of modern multiprocessing machines. In this paper, we propose constructs to specify I/O operations for distributed data structures in the context of Vienna Fortran. These operations can be used by the programmer to provide information which can help the compiler and runtime environment make the most efficient use of the I/O subsystem. 1 Introduction Distributed memory multiprocessors (DMMPs), such as Intel's Paragon and Thinking Machines' CM..