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prefetching in file systems for mimd multiprocessorsThe question of whether prefetching blocks on the file into the block cache can effectively reduce overall execution time of a parallel computation, even under favorable assumptions, is considered. Experiments have been conducted with an interleaved file system testbed on the Butterfly Plus multiprocessor. Results of these experiments suggest that (1) the hit ratio, the accepted measure in traditional caching studies, may not be an adequate measure of performance when the workload consists of parallel computations and parallel file access patterns, (2) caching with prefetching can significantly improve the hit ratio and the average time to perform an I/O (input/output) operation, and (3) an improvement in overall execution time has been observed in most cases. In spite of these gains, prefetching sometimes results in increased execution times (a negative result, given the optimistic nature of the study). The authors explore why it is not trivial to translate savings on individual I/O requests into consistently better overall performance and identify the key problems that need to be addressed in order to improve the potential of prefetching techniques in the environment.
Document ID
19900050527
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Kotz, David F.
(Duke Univ. Durham, NC, United States)
Ellis, Carla Schlatter
(Duke University Durham, NC, United States)
Date Acquired
August 14, 2013
Publication Date
April 1, 1990
Publication Information
Publication: IEEE Transactions on Parallel and Distributed Systems
Volume: 1
ISSN: 1045-9219
Subject Category
COMPUTER SYSTEMS
Funding Number(s)
CONTRACT_GRANT: NCC2-560
CONTRACT_GRANT: NSF CCR-87-21781
CONTRACT_GRANT: NSF CCR-88-21809
Distribution Limits
Public
Copyright
Other