GENERALIZED PARALLEL PROGRAMMING WITH DIVIDE-AND-CONQUER: THE BEEBLEBROX SYSTEM
A. J. Piper and R. W. Prager
JULY 1993
Object-oriented programming has been widely proposed as a discipline suited to extracting parallelism from a program. However, object-oriented programming provides no more guarantee of efficient parallelism than procedural programming. The divide-and-conquer (D&C) algorithm does guarantee a measure of efficient parallelism as demonstrated by many researchers. We present a system that uses object-oriented techniques to encapsulate the D&C algorithm and which is much more flexible than our previous work. We go on to describe a stack-based evaluation algorithm that allows the nesting of D&C evaluations. We use this framework to implement a tree-based language model which gives good parallel performance. We then present some techniques for achieving better performance and which are universally applicable to D&C problems. Finally we analyse the performance in theoretical terms and show that a suitable implementation can achieve better speedup than N/log_2N.
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