Retroactive Subsumption-Based Tabled Evaluation of Logic Programs

• Type: Article in International Conference Proceedings Book
• Date: 2010

Authors

Flavio Cruz (Author) FCUP; Ricardo Rocha (Author) FCUP

Conference proceedings International

Title: LOGICS IN ARTIFICIAL INTELLIGENCE, JELIA 2010

Pages: 130-142

12th European Conference on Logics in Artificial Intelligence (JELIA)

Helsinki, FINLAND, SEP 13-15, 2010

Indexing

ISI Web of Knowledge - 4 Citations

Scopus - 4 Citations

Scientific classification

FOS: Natural sciences > Computer and information sciences

Other information

Authenticus ID: P-003-BWE

DOI: 10.1007/978-3-642-15675-5_13

Abstract (EN): Tabled evaluation is a recognized and powerful implementation technique that overcomes some limitations of traditional Prolog systems in dealing with recursion and redundant sub-computations. Tabling based systems use call similarity to determine if a tabled subgoal will produce their own answers or if it will consume from another subgoal. While call variance has been a very popular approach, call subsumption can yield superior time performance and space improvements as it allows greater reuse of answers. However, the call order of the subgoals can greatly affect the success and applicability of the call subsumption technique. In this work, we present an extension, named Retroactive Call Subsumption, that supports call subsumption by allowing full sharing of answers between subsumed/subsuming subgoals, independently on the order in which they are called. Our experiments using the YapTab tabling engine show considerable gains in evaluation time for some applications, at the expense of a very small overhead for the programs that cannot benefit from it.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 13