@InProceedings{bitton:schedule,
  author = {Dina Bitton},
  title = {Arm Scheduling in Shadowed Disks},
  booktitle = {Proceedings of IEEE Compcon},
  year = {1989},
  month = {Spring},
  pages = {132--136},
  keywords = {parallel I/O, disk shadowing, reliability, disk mirroring, disk
  optimization, pario-bib},
  comment = {Goes further than bitton:shadow. Uses simulation to verify results
  from that paper, which were expressions for the expected seek distance of
  shadowed disks, using shortest-seek-time arm scheduling. Problem is her
  assumption that arm positions stay independent, in the face of correlating
  effects like writes, which move all arms to the same place. Simulations match
  model only barely, and only in some cases. Anyway, shadowed disks can improve
  performance for workloads more than 60 or 70\% reads.}
}