Effectiveness of Producer-Initiated Communication

Producer-initiated communication mechanisms have been proposed to reduce communication latency in distributed shared memory systems. These mechanisms aim to move data close to its consumers, as soon as it is produced. The data is then available locally when needed by the consumer, avoiding the latency of retrieving it from global memory or from the producer’s cache. Studies have shown that these sorts of mechanisms are effective, in that they reduce latency and improve execution time, compared to plain invalidate-based cache coherence. It is not clear, however, whether producer-initiated mechanisms provide a significant advantage over prefetch or other consumer-oriented mechanisms designed to hide or reduce latency. In the following sections, we look at the published evidence and draw some conclusions.