A Hybrid Hardware/Software Generated Prefetching Thread Mechanism on Chip Multiprocessors

This paper proposes a hybrid hardware/software generated prefetching thread mechanism on Chip Multiprocessors(CMP). Two kinds of prefetching threads appear in our hybrid mechanism. Most threads belong to Dynamic Prefetching Thread, which are automatically generated, triggered, spawn and managed by hardware; The others are of Static Prefetching Thread, targeting at the critical delinquent loads which can not be accurately or timely predicted by Dynamic Prefetching Thread. Static Prefetching Threads are statically generated by binary-level optimization tool with the guide of profiling information. Also, some aggressive thread construction policies are proposed. Furthermore, the necessary hardware infrastructure for CMP supporting this hybrid mechanism are described. For a set of memory limited benchmarks with complicated access patterns, an average speedup of 3.1% is achieved on dual-core CMP when constructing basic hardware-generated prefetching thread, and this gain grows to 31% when adopting our hybrid mechanism.