Pseudo - File - Systems

This paper describes a facility that transparently extends the Sprite distributed file system to include foreign file systems and arbitrary user services. A pseudo-filesystem is a sub-tree of the distributed hierarchical name space that is implemented by a user-level server process. A pseudo-file-system fits naturally into the Sprite distributed system; the server runs on one host and access from other hosts is handled in the same way as remote access to Sprite file servers. The pseudo-file-system interface is general enough to be used for version control systems, access to archival storage, as well as access to other kinds of file systems. We currently use a pseudofile-system server to provide access to NFS file servers from Sprite workstations. Performance results of the NFS server are given in order to evaluate the cost associated with user-level implementation of services. †