zFS (IBM file system)
|Full name||z/OS Distributed File Service System z File System|
|Introduced||1995 (as DCE DFS Local File System for MVS/ESA V5R2.2)|
|Max. filename length||?|
|Supported operating systems||z/OS (all releases), OS/390 (all releases), MVS/ESA V5R2.2|
zFS refers to two different IBM file systems:
- zFS most often refers to z/OS Distributed File Service zSeries File System, the newest POSIX-style hierarchical file system for IBM's z/OS operating system, a successor to that operating system's HFS. zFS, as a separate entity, was initially released as PTFs (patches) for z/OS 1.2 with backports available for z/OS 1.1 and OS/390 2.10. Beginning with z/OS 1.3, zFS is included as a standard feature and is being actively developed. However, zFS was actually first released in 1995 as the Local File System, a lower layer of the DCE Distributed File System. It was available on MVS/ESA V5R2.2 and all OS/390 releases. DFS/LFS was provided as a part of the DCE feature, not of the base operating system as in z/OS.
- zFS was also an IBM research project to develop a distributed, decentralized file system. It was a follow-on to the IBM DSF (Data Sharing Facility) project to build a serverless file system.
Neither file system has any relation to Oracle/Sun's ZFS.