9309176 Griffioen This research project to address the issues involved in the design of scalable high-performance distributed file systems based on volatile storage. The flexibility of such system combined with recent technology trends provides an opportunity for exceptional performance and superior resource utilization. The research has four components. First, a new distributed file system abstraction that incorporates both volatile and stable storage into a single abstraction will be investigated. The abstraction allows users to adjust the persistence guarantees of a file to match the requirements of the application, thereby optimizing performance. Second, a novel memory architecture called loosely-coupled memory that provides a massive aggregate memory space for use by the proposed file system will be introduced. The architecture also incorporates asymmetric compression techniques to make effective use of memory and underutilized processing power, and to improve file system access time. Third, a new abstraction and file system architecture into the BM Xinu operating system to verify our design. VM Xinu provides a high-performance, low-latency communication protocol ideal for support of a loosely-coupled memory system. Finally, the file system will be incorporated into the Mach operating system to demonstrate and evaluate our ideas in the context of a large user population. ***
