Implementation and evaluation of a multimedia file system

The paper describes the implementation and evaluation of MMFS, a Multimedia File System that extends the UNIX File System (UFS) specifically for interactive multimedia applications. MMFS supports a two-dimensional file structure for single-medium editing and multiple-media playback environments. The API allows the communication of application-specific information to MMFS for performance optimization. MMFS significantly improves interactive playback performance by supporting intelligent prefetching and state-based caching, prioritized real-time disk scheduling, and synchronized multi-stream retrieval. In addition to improved response time for VCR-like playback modes, the MMFS optimizations lead to minimal synchronization skew during multi-stream retrievals, and orders-of-magnitude reduction in response time for editing operations, when compared to UFS.