Parallel Game-Tree Search

Parallel Game Tree Search on SIMD Machines

We describe an approach to the parallelization of game tree search on SIMD machines. It turns out that the single-instruction restriction of SIMD-machines is not a big obstacle for achieving eeciency. We achieve speedups up to 5850 on a 16K processor MasPar MP-1 if the search trees are suuciently large and if there are no strong move ordering heuristics. To our best knowledge, the largest speed...

APHID: Asynchronous Parallel Game-Tree Search

Most parallel game-tree search approaches use synchronous methods, where the work is concentrated within a specific part of the tree, or at a given search depth. This article shows that asynchronous game-tree search algorithms can be as efficient as or better than synchronous methods in determining the minimax value. APHID, a new asynchronous parallel game-tree search algorithm, is presented. A...

A Taxonomy of Parallel Game-Tree Search Algorithms

Performance Analysis of Two Parallel Game-Tree Search Applications

Game-tree search plays an important role in the field of artificial intelligence. In this paper we analyze scalability performance of two parallel game-tree search applications in chess on two shared-memory multiprocessor systems. One is a recently-proposed Parallel Randomized Best-First Minimax search algorithm (PRBFM) in a chess-playing program, and the other is Crafty, a state-of-the-art alp...

Distributed Game Tree Search on a Massively Parallel System

During the World Computer Chess Championships in Madrid, November 1992, our distributed chess program ZUGZWANG ran on a 1024 processor machine and nished second place without having lost a game. This article presents measurements that show the behaviour of ZUGZWANG using massive parallelism. We will show that the network used to interconnect the processors is a crucial point for the eeciency of...