§' Departamento de hrformática Distributed Multi-Threading in GNU Prolog Nuno Eduardo Quaresma Morgadinho <
[email protected]> Supervisor: Salvador Abreu (Ur,iversidade de Évora DI) This thesis does not include aVpreciation nor suggestions madeby the iury. Esta dissertaçã.o não inclui as críticas e sugestões feitas pelo iúri, Évora 2007 § Departamento de Lrformática Distributed Multi-Threading in GNU Prolog Nuno Eduardo Quaresma Morgadinho <
[email protected]> ..--# Jü3 3?Y Supervisor: Salvador Abreu (Universidade de Évora, DI) This thesis does not include appreciation nor suggestions madeby tlrc jury. Esta dissertação não inclui as críticas e sugestões feitas pelo júri. Évora 2007 Abstract Although parallel computing has been widely researdred, the process of bringrng concurrency and parallel programming to the mainstream has just be- gun. Combining a distributed multi-threading environment like PM2 with Pro- log, opens the way to exploit concurrency and parallel computing using logic programming. Tlo achieve suú a pu{pose, we developed PM2-Prolog, a Prolog interface to the PM2 system. It allows multithreaded Prolog applications to run in multiple GNU Prolog engines in a distributed environment, thus taking advan- tage of the resources available on a computer network. This is especially useful for computationally intensive problems, where performance is an important fac- tor. The system API offers thread management primitives, as well as explicit communication between threads. Preliminary test results show an almost linear speedup, when compared to a sequential version. Keywords: Distributed, Multi-Threading, Prolog, Logic Programming, Concurrency, Parallel, High-PerformÉulce Computing 1 Resumo Multi-Threading Distribuído no GNU Prolog Embora a computação paralela já tenha sido alvo de inúmeros estudos, o processo de a tomar acessível às massas ainda mal começou.