Two processor scheduling is in NC

  • David Helmbold
  • Ernst Mayr
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 227)


We present a parallel algorithm for the two processor scheduling problem. This algorithm constructs an optimal schedule for unit execution time task systems with arbitrary precedence constraints using a polynomial number of processors and running in time polylog in the size of the input. Whereas previous parallel solutions for the problem made extensive use of randomization, our algorithm is completely deterministic and based on an interesting iteration technique. It is of independent relevance for two more reasons. It provides another example for the apparent difference in complexity between decision and search problems in the context of fast parallel computation, and it gives an NC-algorithm for the matching problem in certain restricted cases.


Schedule Problem Optimal Schedule Precedence Constraint Interval Graph Maximum Match 
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 1986

Authors and Affiliations

  • David Helmbold
    • 1
  • Ernst Mayr
    • 1
  1. 1.Department of Computer ScienceStanford UniversityUSA

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