Efficient replacement of nonuniform objects in Web caches

Abstract

Cache performance depends heavily on replacement algorithms, which dynamically select a suitable subset of objects for caching in a finite space. Developing such algorithms for wide-area distributed environments is challenging because, unlike traditional paging systems, retrieval costs and object sizes are not necessarily uniform. In a uniform caching environment, a replacement algorithm generally seeks to reduce cache misses, usually by replacing an object with the least likelihood of rereference. In contrast, reducing total cost incurred due to cache misses is more important in nonuniform caching environments.