A survey of PRAM simulation techniques

Abstract

The Parallel Random Access Machine (PRAM) is an abstract model of parallel computation which allows researchers to focus on the essential characteristics of a parallel architecture and ignore other details. The PRAM has long been acknowledged to be a useful tool for the study of parallel computing, but unfortunately it is not physically implementable in hardware. In order to take advantage of the broad base of algorithms and results regarding this high-level abstraction one needs general methods for allowing the execution of PRAM algorithms on more realistic machines. In the following we survey these methods, which we refer to as PRAM simulation techniques. The general issues of memory management and routing are discussed, and both randomized and deterministic solutions are considered. We show that good theoretical solutions to many of the subproblems in PRAM simulation have been developed, though questions still exist as to their practical utility. This article should allow those performing research in this field to become well acquainted with the current state of the art, while allowing the novice to get an intuitive feeling for the fundamental questions being considered. The introduction should provide a concise tutorial for those unfamiliar with the problem of PRAM simulation.