Threads and Or-Parallelism Unified

TL;DR

This paper presents a redesigned multi-threaded YapOr system that efficiently exploits or-parallelism in logic programming, achieving near-linear speedups on multi-core architectures by sharing core components and optimizing execution.

Contribution

The paper introduces a novel multi-threaded implementation of YapOr that leverages shared data structures and the YAP Prolog engine to improve parallel execution efficiency.

Findings

Achieves almost linear speedups on most applications

Effectively exploits implicit parallelism in multi-core architectures

Redesigns YapOr for shared environment and optimized performance

Abstract

One of the main advantages of Logic Programming (LP) is that it provides an excellent framework for the parallel execution of programs. In this work we investigate novel techniques to efficiently exploit parallelism from real-world applications in low cost multi-core architectures. To achieve these goals, we revive and redesign the YapOr system to exploit or-parallelism based on a multi-threaded implementation. Our new approach takes full advantage of the state-of-the-art fast and optimized YAP Prolog engine and shares the underlying execution environment, scheduler and most of the data structures used to support YapOr's model. Initial experiments with our new approach consistently achieve almost linear speedups for most of the applications, proving itself as a good alternative for exploiting implicit parallelism in the currently available low cost multi-core architectures.