@InProceedings{itoh:pimos,
  author = {Fumihide Itoh and Takashi Chikayama and Takeshi Mori and Masaki
  Sato and Tatsuo Kato and Tadashi Sato},
  title = {The Design of the {PIMOS} File System},
  booktitle = {Proceedings of the International Conference on Fifth Generation
  Computer Systems},
  year = {1992},
  volume = {1},
  pages = {278--285},
  organization = {ICOT},
  keywords = {parallel file system, pario-bib},
  comment = {File system in the PIMOS operating system for the PIM (Parallel
  Inference Machine) in the Fifth Generation Computer Systems project in Japan.
  Paper design, no results yet. Uses disks that are attached directly to the
  computational processors. Significant in that it does use client caches in a
  parallel file system. Caches are kept coherent with a centralized
  directory-based protocol for exclusive-writer, multiple-reader semantics,
  supporting sequential consistency. Disk management includes logging to
  surivive crashes. Bitmap free list with buddy system to support full, 1/2,
  and 1/4 blocks. Trick to avoid constant update of on-disk free list. My
  suspicion is that cache coherence protocol may be expensive, especially in
  larger systems.}
}