Speeding up constraint propagation

Christian Schulte, Peter J. Stuckey

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearchpeer-review

35 Citations (Scopus)


This paper presents a model and implementation techniques for speeding up constraint propagation. Two fundamental approaches to improving constraint propagation are explored: keeping track of which propagators are at fixpoint, and choosing which propagator to apply next. We show how idempotence reasoning and events help track fixpoints more accurately. We improve these methods by using them dynamically (taking into account current domains to improve accuracy). We define priority-based approaches to choosing a next propagator and show that dynamic priorities can improve propagation. We illustrate that the use of multiple propagators for the same constraint can be advantageous with priorities, and introduce staged propagators which combine the effects of multiple propagators with priorities for greater efficiency.

Original languageEnglish
Title of host publicationPrinciples and Practice of Constraint Programming – CP 2004
Subtitle of host publication10th International Conference, CP 2004 Toronto, Canada, September 27 - October 1, 2004 Proceedings
EditorsMark Wallace
Place of PublicationBerlin Germany
Number of pages15
ISBN (Print)3540232419
Publication statusPublished - 1 Dec 2004
Externally publishedYes
EventInternational Conference on Principles and Practice of Constraint Programming 2004 - Toronto, Canada
Duration: 27 Sept 20041 Oct 2004
Conference number: 10th

Publication series

NameLecture Notes in Computer Science
ISSN (Print)0302-9743


ConferenceInternational Conference on Principles and Practice of Constraint Programming 2004
Abbreviated titleCP 2004

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