Abstracts - 1997 ANNUAL TECHNICAL CONFERENCE
An Analytical Approach to File Prefetching
Hui Lei and Dan Duchamp
Computer Science Department
Columbia University, New York, NY 10027
Abstract
File prefetching is an effective technique for improving file access
performance. In this paper, we present a
file prefetching mechanism that is based on on-line analytic
modeling of interesting system events and is transparent to higher levels.
The mechanism, incorporated into a client's file cache manager, seeks
to build semantic structures that capture
the intrinsic correlations between file accesses. It then heuristically
uses these structures to represent distinct file usage patterns and
exploits them to prefetch files from a file server.
We show results of a simulation study and of a
working implementation. Measurements suggest that our method
can predict future file accesses with an accuracy around 90%, that
it can reduce cache miss rate by up to 47% and application latency by
up to 40%. Our method imposes little overhead, even under antagonistic
circumstances.
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