Andorra-I engine: A parallel implementation of the basic Andorra model

• Type: Article in International Conference Proceedings Book
• Date: 1991

Authors

Vitor Santos Costa (Author) FCUP; Warren David, HD (Author) Other; Rong Yang (Author) Other

Conference proceedings International

Title: Logic Programming, Proceedings of the Eigth International Conference, Paris, France, June 24-28, 1991

Pages: 825-839

Logic Programming - Proceedings of the 8th International Conference

Paris, Fr, 24 June 1991 through 28 June 1991

Indexing

Scopus - 35 Citations

Other information

Authenticus ID: P-007-5E4

Abstract (EN): Andorra-I is an experimental parallel Prolog system that transparently exploits both dependent and-parallelism and or-parallelism. It constitutes the first implementation of the Basic Andorra model, a parallel execution model for logic programs in which determinate goals are executed before other goals. This model, besides combining two of the most important forms of implicit parallelism in logic programs, also provides a form of implicit coroutining. This means that Andorra-I not only supports standard Prolog but also provides the capabilities of flat committed-choice languages. In this paper, we discuss the main issues involved in the implementation of the Andorra-I engine, covering both the sequential version which runs on uniprocessors and the parallel version which runs on shared-memory multiprocessors such as Sequent Symmetry. We then present performance data for our implementation. This data shows that Andorra-I, an interpreter, has a single-processor performance similar to the comparable sequential system, C-Prolog, while on multiple processors Andorra-I is able to obtain good speedups from both and-parallelism and or-parallelism. In suitable cases, the speedup obtained from exploiting both forms of parallelism combined is better than that obtainable from exploiting either kind alone.

Language: English

Type (Professor's evaluation): Scientific