An Adaptive Cache Coherence Protocol Optimized for Producer-Consumer Sharing

Shared memory multiprocessors play an increasingly important role in enterprise and scientific computing facilities. Remote misses limit the performance of shared memory applications , and their significance is growing as network latency increases relative to processor speeds. This paper proposes two mechanisms that improve shared memory performance by eliminating remote misses and/or reducing the amount of communication required to maintain coherence. We focus on improving the performance of applications that exhibit producer-consumer sharing. We first present a simple hardware mechanism for detecting producerconsumer sharing. We then describe a directory delegation mechanism whereby the “home node” of a cache line can be delegated to a producer node, thereby converting 3-hop coherence operations into 2-hop operations. We then extend the delegation mechanism to support speculative updates for data accessed in a producer-consumer pattern, which can convert 2-hop misses into loc...

• Type: Conference
• Year: 2007
• Where: HPCA
• Authors: Liqun Cheng, John B. Carter, Donglai Dai
• Keywords: Computer Architecture, HPCA 2007, Producer-consumer Sharing, Remote Misses, Shared Memory