sfs: AParallel File System for the CM-5

This paper describes the creation of a Unix-compatible le system with highly scalable performance and size. The le system is on the CM-5 backed by a scalable array of disks. Using the Unix le system (UFS) from the SunOS 4.1.2 kernel as a base and modifying it to support Connection Machine (CM) operations, we have created a new le system, the scalable le system, or sfs. We discuss the CM operations we support, such as parallel reads and writes to the processing nodes of the Connection Machine, the use of NFS to support many partitions of processing nodes on the CM, support for very large le sizes (64-bit) and support for odd numbers of disk drives. The tradeo s and decisions made during the course of this project as well as performance data for varying numbers of disk drives are provided.