Partial match retrieval in two-headed disks

  • Yannis Manolopoulos
  • Athena Vakali
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 978)


The performance of a disk with two heads per surface separated by a fixed number of cylinders is examined. We derive the probability distribution of arm stops, the expected number of stops as well as the expected number of cylinder clusters, i.e. the number of sets of consecutive compound cylinders. In comparison with a single-headed disk, it is shown that the performance gain may reach 50% on the average.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Yannis Manolopoulos
    • 1
  • Athena Vakali
    • 1
  1. 1.Department of InformaticsAristotle UniversityThessalonikiGreece

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