Separating the power of EREW and CREW PRAMs with small communication width

  • Paul Beame
  • Faith E. Fich
  • Rakesh K. Sinha
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 709)


We prove that evaluating a Boolean decision tree of height h requires Ω(h/log*h) time on any EREW PRAM with communication width one. Since this function can be easily solved in time O(√h) on a CREW PRAM with communication width one, this gives a separation between the two models. Our result can be extended to show a separation whenever the EREW PRAM has communication width m ε o(√h).


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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • Paul Beame
    • 1
  • Faith E. Fich
    • 2
  • Rakesh K. Sinha
    • 1
  1. 1.Computer Science and EngineeringUniversity of WashingtonSeattleUSA
  2. 2.Computer ScienceUniversity of TorontoTorontoCanada

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