Lazy Set-Sharing Analysis: 8th International Symposium, FLOPS 2006, Fuji-Susono, Japan, April 24-26, 2006. Proceedings

Sharing analysis is widely deployed in the optimisation, specialisation and parallelisation of logic programs. Each abstract unification operation over the classic Jacobs and Langen domain involves the calculation of a closure operation that has exponential worst-case complexity. This paper explores a new tactic for improving performance: laziness. The idea is to compute partial sharing information eagerly and recover full sharing information lazily. The net result is an analysis that runs in a fraction of the time of the classic analysis and yet has comparable precision

DeWiz – A Modular Tool Architecture for Parallel Program Analysis

Abstract. Tool support is an important factor for efficient development of parallel programs. Due to different goals, target systems, and levels of abstraction, many specialized tools and environments have been developed. A contrary approach in the area of parallel program analysis is offered by DeWiz, which focuses on unified analysis functionality based on the event graph model. The desired analysis tasks are formulated as a set of graph filtering and transformation operations, which are implemented as independent analysis modules. The concrete analysis strategy is composed by placing these modules on arbitrary networked machines, arranging and interconnecting them. The resulting DeWiz system processes the data stream to extract useful information for program analysis.

Experiments in Parallel Constraint-Based Local Search

International audienceWe present a parallel implementation of a constraint-based local search algorithm and investigate its performance results on hardware with several hundreds of processors. We choose as basic constraint solving algorithm for these experiments the "adaptive search" method, an efficient sequential local search method for Constraint Satisfaction Problems. The implemented algorithm is a parallel version of adaptive search in a multiple independent-walk manner, that is, each process is an independent search engine and there is no communication between the simultaneous computations. Preliminary performance evaluation on a variety of classical CSPs benchmarks shows that speedups are very good for a few tens of processors, and good up to a few hundreds of processors