A parallel implementation for AKL

  • Remco Moolenaar
  • Bart Demoen
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 714)


This paper describes the design of an AND/OR parallel implementation called ParAKL, for the Andorra Kernel Language. The design is inspired by the Warren Abstract Machine with some important extensions. One of the main problems in AND/ OR parallel systems is the efficient handling of variables. We have adopted the PEPSys hashing scheme with additional mechanisms for the notion of quietness required by the theoretical model of AKL. A ParAKL computation builds a tree representing the branches of the search tree currently under execution. This tree is built in the usual WAM-like way until a processor blocks and is scheduled to other work. A scheduled branch is separated from the original branch using a hash window, in which bindings made to shared variables are saved.


AND/OR parallelism Andorra Andorra Kernel Language 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • Remco Moolenaar
    • 1
  • Bart Demoen
    • 1
  1. 1.Department of Computing ScienceK.U.LeuvenBelgium

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