Web Caching and Replication

12.2. Performance Bounds of Prefetching

There is substantial danger in prefetching. It is inherently difficult to predict the future actions of a user who does not provide any special information to the prefetcher, and incorrect guesses impose extra load on shared facilities. Therefore, it is valuable to know how much possible advantage prefetching can deliver and how accurate prefetching must be in order to succeed.

An important study by Kroeger et al. [1997] establishes bounds on the latency reduction achievable by prefetching into a shared proxy cache. These are not mathematical bounds, but rather the results of simulations applied to substantial traces (approximately 24.6 million requests) under idealized conditions. Their most notable result ...