A Multiprocessor Extension to the Conventional File System Interface

As the I/O needs of parallel scienti c applications increase, le systems for multiprocessors are being designed to provide applications with parallel access to multiple disks. Many parallel le systems present applications with a conventional Unix-like interface that allows the application to access multiple disks transparently. By tracing all the activity of a parallel le system in a production, scienti c computing environment, we show that many applications exhibit highly regular, but non-consecutive I/O access patterns. Since the conventional interface does not provide an e cient method of describing these patterns, we present an extension which supports strided and nested-strided I/O requests.