Swapping Evaluation: A Memory-Scalable Solution for Answer-On-Demand Tabling

One of the differences among the various approaches to suspension-based tabled evaluation is the scheduling strategy. The two most popular strategies are local and batched evaluation. The former collects all the solutions to a tabled predicate before making any one of them available outside the tabled computation. The latter returns answers one by one before computing them all, which in principle is better if only one answer (or a subset of the answers) is desired. Batched evaluation is closer to SLD evaluation in that it computes solutions lazily as they are demanded, but it may need arbitrarily more memory than local evaluation, which is able to reclaim memory sooner. Some programs which in practice can be executed under the local strategy quickly run out of memory under batched evaluation. This has led to the general adoption of local evaluation at the expense of the more depth-first batched strategy. In this paper we study the reasons for the high memory consumption of batched eva...

• Type: Journal
• Year: 2010
• Where: CORR
• Authors: Pablo Chico de Guzmán, Manuel Carro, David Scott Warren
• Keywords: CORR 2010, Education, Evaluation, Scheduling Strategy, Suspension-based Tabled Evaluation