Pursuing the Performance Potential of Dynamic Cache Line Sizes *

In this paper we examine the application of offline algorithms for determining the optimal sequence of loads and superloads (a load of multiple consecutive cache lines) for direct-mapped caches. We evaluate potential gains in terms of miss rate and bandwidth and find that in many cases optimal superloading can noticeably reduce the miss rate without appreciably increasing bandwidth. Then we examine how this performance potential might be realized. We examine the effectiveness of a dynamic online algorithm and of static analysis (profiling) for superloading and compare these to next-line prefetching. Experimental results show improvements comparable to those of the optimal algorithm in terms of miss rates