A Subterm-Based Global Trie for Tabled Evaluation of Logic Programs

• Type: Article in International Conference Proceedings Book
• Date: 2011

Authors

Joao Raimundo (Author) Other; Ricardo Rocha (Author) FCUP

Conference proceedings International

Title: PROGRESS IN ARTIFICIAL INTELLIGENCE

Pages: 239-253

15th Portuguese Conference on Artificial Intelligence (EPIA 2011)

Lisbon, PORTUGAL, OCT 10-13, 2011

Indexing

ISI Web of Knowledge - 0 Citations

Scopus - 0 Citations

Scientific classification

FOS: Natural sciences > Computer and information sciences

Other information

Authenticus ID: P-002-VYB

DOI: 10.1007/978-3-642-24769-9_18

Abstract (EN): Tabling is an implementation technique that overcomes some limitations of traditional Prolog systems in dealing with redundant sub-computations and recursion. A critical component in the implementation of an efficient tabling system is the design of the table space. The most popular and successful data structure for representing tables is based on a two-level trie data structure, where one trie level stores the tabled subgoal calls and the other stores the computed answers. The Global Trie (GT) is an alternative table space organization designed with the intent to reduce the tables's memory usage, namely by storing terms in a global trie, thus preventing repeated representations of the same term in different trie data structures. In this paper, we propose an extension to the GT organization, named Global Trie for Subterms (GT-ST), where compound subterms in term arguments are represented as unique entries in the GT. Experimental results using the Yap Tab tabling system show that GT-ST support has potential to achieve significant reductions on memory usage, for programs with increasing compound subterms in term arguments, without compromising the execution time for other programs.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 15