, Volume 12, Issue 2–3, pp 209–224 | Cite as

String layouts for a redundant array of inexpensive disks

  • L. Newberg
  • D. Wolfe


This article introduces the concept of abad square in aredundant array of inexpensive disks (RAID). Bad squares are used to prove upper limits on the reliability of the2d-parity arrangement when there is the possibility that astring of disks may fail simultaneously. Bad-square analysis motivates several optimal string layouts which achieve these limits. Bad squares also provide a means to calculate the mean time to data loss for a RAID layout, without the use of Monte Carlo simulation.

Key words

RAID Disk array 2d-Parity Fault tolerance Disk strings Bad square 


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Copyright information

© Springer-Verlag New York Inc. 1994

Authors and Affiliations

  • L. Newberg
    • 1
  • D. Wolfe
    • 1
  1. 1.University of CaliforniaBerkeleyUSA

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