Multiprocessor File System Interfaces

Increasingly, file systems for multiprocessors are designed with parallel access to multiple disks, to keep I/O from becoming a serious bottleneck for parallel applications. Although file system software can transparently provide high-performance access to parallel disks, a new file system interface is needed to facilitate parallel access to a file from a parallel application. We describe the difficulties faced when using the conventional (Unix-like) interface in parallel applications, and then outline ways to extend the conventional interface to provide convenient access to the file for parallel programs, while retaining the traditional interface for programs that have no need for explicitly parallel file access. Our interface includes a single naming scheme, a \em multiopen\/ operation, local and global file pointers, mapped file pointers, logical records, \em multifiles, and logical coercion for backward compatibility