language: en

[To appear in Parallel Computing, 1997.]

[Available at URL]

The Galley Parallel File System

Nils Nieuwejaar, David Kotz
fnils,dfkg@cs.dartmouth.edu
Department of Computer Science, Dartmouth College,
Hanover, NH 03755-3510

Most current multiprocessor file systems are designed to use multiple disks in parallel, using the high aggregate bandwidth to meet the growing I/O requirements of parallel scientific applications. Many multiprocessor file systems provide applications with a conventional Unix-like interface, allowing the application to access multiple disks transparently. This interface conceals the parallelism within the file system, increasing the ease of programmability, but making it difficult or impossible for sophisticated programmers and libraries to use knowledge about their I/O needs to exploit that parallelism. In addition to providing an insufficient interface, most current multiprocessor file systems are optimized for a different workload than they are being asked to support. We introduce Galley, a new parallel file system that is intended to efficiently support realistic scientific multiprocessor workloads. We discuss Galley's file structure and application interface, as well as the performance advantages offered by that interface.

Key words: Parallel I/O. Multiprocessor file system. Performance evaluation. IBM SP-2. Scientific Computing.

1 Introduction