Temporal analysis of cache prefetching strategies for multimedia applications

Prefetching is a widely adopted technique for improving performance of cache memories. Performances are typically affected by the design parameters, such as cache size and associativity, but also by the type of locality embodied in the programs. In particular multimedia tools and programs handling images and video are characterized by a bi-dimensional spatial locality that could be greatly exploited by the inclusion of prefetching in the cache architecture. In this paper we compare some prefetching techniques for multimedia programs (such as MPEG compression, image processing, visual object segmentation) by performing a detailed evaluation of the memory access time. The goal is to prove that a significant speedup can be achieved by using either standard prefetching techniques (such as OBL or adaptive prefetching) or some innovative and image-oriented prefetching methods like the neighbor prefetching described in the paper. Performance are measured with the PRIMA trace-driven simulator.