Removal Policies in Network Caches for World-Wide Web Documents

World-Wide Web proxy servers that cache documents can potentially reduce three quantities: the number of requests that reach popular servers, the volume of network trac resulting from document requests, and the latency that an end-user experiences in retrieving a document. This paper examines the rst two using the measures of cache hit rate and weighted hit rate (or fraction of client-requested bytes returned by the proxy). A client request for an uncached document may cause the removal of one or more cached documents. Variable document sizes and types allow a rich variety of policies to select a document for removal, in contrast to policies for CPU caches or demand paging, that manage homogeneous objects. We present a taxonomy of removal policies. Through trace-driven simulation, we determine the maximum possible hit rate and weighted hit rate that a cache could ever achieve, and the removal policy that maximizes hit rate and weighted hit rate. The experiments use ve traces of 37 t...

• Type: Conference
• Year: 1996
• Where: SIGCOMM
• Authors: Marc Abrams, Charles R. Standridge, Ghaleb Abdulla, Edward A. Fox, Stephen Williams
• Keywords: Cache Hit Rate, Communications, Hit Rate, Maximizes Hit Rate, SIGCOMM 1996