Memory access in models of parallel computation: From folklore to synergy and beyond

  • Selim G. Akl
Session 4 Invited Presentation
Part of the Lecture Notes in Computer Science book series (LNCS, volume 519)


We investigate various aspects of the role played by memory in the parallel random access machine (PRAM) model. Three results are obtained, each exhibiting a different consequence of the power of concurrent memory access in the PRAM: (i) two folk theorems are revisited and found not to hold for a class of inherently parallel problems; (ii) for a wide family of computations, the amount of work done by a parallel solution is shown to be smaller than that done by the best possible sequential one; and (iii) a model of computation is introduced which is an extension of the strongest variant of the PRAM, yet it requires no more resources than its weakest variant.


Memory Access Parallel Algorithm Shared Memory Memory Location Sequential Algorithm 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  • Selim G. Akl
    • 1
  1. 1.Department of Computing and Information ScienceQueen's UniversityKingstonCanada

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