Episode filesystem

Last updated
Episode
Developer(s) Transarc
Full nameEpisode
Introduced1992;30 years ago (1992)
Structures
Directory contents8KB blocks with hash table
File allocationinode-based
Limits
Max. filename length256 bytes
Features
Forks No
AttributesPOSIX
File system permissions POSIX ACLs
Transparent compressionNo
Transparent encryption No
Other
Supported operating systems AIX, Solaris, z/OS

Episode is a POSIX compliant file system most commonly known for its use in DCE/DFS file servers. It was designed to achieve the goals of portability, scaling, and to make more efficient use of available system bandwidth. It used a variety of methods to achieve these goals, one of which was its use of metadata logging, designed to enhance the file system's performance.

The Episode file system is the basis for the IBM z/OS POSIX-compatible file system called zFS. [1]

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References

  1. Rogers, Paul; Conway, Richard. "ABCs of z/OS System Programming: Volume 9" (PDF). Redbooks. IBM. Retrieved 1 May 2022.