New simulations between CRCW PRAMs

  • Bogdan S. Chlebus
  • Krzysztof Diks
  • Torben Hagerup
  • Tomasz Radzik
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 380)


This paper is part of a continued investigation of the relative power of different variants of the CRCW PRAM with infinite global memory. The models that we consider are the standard Priority and Common PRAMs, together with the less well-known Collision+ and Tolerant PRAMs. We describe several new results for the simulation of an n-processor Priority PRAM on weaker machines:
  1. (1)

    on an n-processor Tolerant PRAM: Slowdown \(O\left( {\sqrt {log{\text{ }}n} } \right)\);

  2. (2)

    on an n-processor Collision+ PRAM: Slowdown O(log log n log(3)n);

  3. (3)

    on a Common PRAM with kn processors (k≤log n/2): Slowdown O(log n/(k log(log n/k)));

  4. (4)

    on a Tolerant PRAM with kn processors (2≤k≤log n): Slowdown O(log n/log k);

  5. (5)

    on a randomized n-processor Collision+ PRAM: Expected slowdown O(log log n).



Active Node Global Memory Partitioning Problem Input Array Main Processor 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • Bogdan S. Chlebus
    • 1
  • Krzysztof Diks
    • 1
  • Torben Hagerup
    • 2
  • Tomasz Radzik
    • 3
  1. 1.Instytut InformatykiUniwersytet Warszawski, PKiN, p. 850WarszawaPoland
  2. 2.Fachbereich InformatikUniversität des SaarlandesSaarbrückenWest Germany
  3. 3.Computer Science DepartmentStanford UniversityStanford

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