FORTRAN for clusters of IBM ES/3090 multiprocessors

IBM Clustered FORTRAN is a combination of software and hardware that allows two IBM Enterprise System/3090™ (ES/3090™) multiprocessors to be physically connected as a cluster and allows FORTRAN jobs to execute in parallel across all of the processors of the cluster. The FORTRAN compiler and library provided as part of Clustered FORTRAN are used for writing and executing the parallel programs in this hybrid environment of distributed and shared-memory systems. The compiler provides language extensions for explicit programming in parallel, as well as the ability to automatically generate both parallel and vector code. The Clustered FORTRAN language allows users to write parallel applications that are independent of the machine configuration and operating system. This paper describes the execution environment, compiler, and library, gives some variations of programming matrix multiplication, and shows that performance of one GigaFLOPS can be achieved using Clustered FORTRAN.