Abstract
This paper gives a short report on the current state of our research into scheduling speculative tasks in the Aurora or-parallel Prolog system. A Speculative task is one that may be pruned by a cut or commit, rendering any work done on that task to be wasted. The use of pruning operators is commonplace in most Prolog applications so there is a need to schedule speculative tasks in a way that avoids wasted work.
Several schedulers have already been developed for the Aurora system but none of the current schedulers make any distinction between speculative and non-speculative work.
We show that by treating speculative work differently it is possible to obtain a significant improvement in performance as measured both by the reduction of wasted work and an improvement in speedups.
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© 1991 Springer-Verlag Berlin Heidelberg
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Beaumont, A. (1991). Scheduling strategies and speculative work. In: Beaumont, A., Gupta, G. (eds) Parallel Execution of Logic Programs. PLP 1991. Lecture Notes in Computer Science, vol 569. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-55038-0_9
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DOI: https://doi.org/10.1007/3-540-55038-0_9
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