The Modula Environment for Parallel Programming

This paper presents a portable parallel program ming environment for Modula an explicitly parallel machine independent extension of Modula Modula o ers synchronous and asynchronous par allelism a global single address space and automatic data and process distribution The Modula system consists of a compiler a debugger a cross architecture make a runtime systems for di erent machines and a set of scalable parallel libraries Implementations exist for the MasPar MP series of massively parallel proces sors SIMD the KSR parallel computer MIMD heterogeneous LANs of workstations MIMD and single workstations SISD The paper presents the important components of the Modula environment and discusses selected imple mentation issues We focus on how we achieve a high degree of portability for our system while at the same time ensuring e ciency