Tolerating Latency by Prefetching Java Objects

In recent years, processor speed has become increasingly faster than memory speed. One technique for improving memory performance is data prefetching which is successful in array-based codes but only now are researchers applying to pointer-based codes. In this paper, we evaluate a data prefetching technique, called greedy prefetching, for tolerating latency in Java programs. In greedy prefetching, when a loop or recursive method updates an object o, we prefetch objects to which o refers. We describe inter- and intraprocedural algorithms for computing objects to prefetch and we present preliminary results showing its effectiveness on a few, small Java programs. Prefetching improves performance, but there is significant room for further improvement.