复杂访问模式下假共享Cache行抖动的消除

ELIMINATING THE FALSE SHARING CACHE LINE THRASHING IN COMPLEX ACCESS PATTERNS

在详细讨论了简单数据组访问模式下假共享抖动现象及其消除方法的基础上，本文着重分析了复杂访问模式下的假共享Ｃａｃｈｅ行抖动现象和真假共享抖动并存现象，引入了并行循环访问距概念，提出了消除假共享抖动的编译方法－块化错位方法。结合块化错位方法，我们提出了多维数组的数组扩展思想，给出了多重嵌套循环含多次写访问情况下减少或消除抖动的算法。

This paper analyzes the false sharing cache line thrashing phenomenon in complex access patterns, introduces the concept of access intervals for parallel loops, and proposes a method called blocking and staggering to eliminate the false sharing thrashing at compile-time. Combining with the blocking and staggering, the idea of array expansion for multidimensional arrays is presented, and the algorithms to reduce or eliminate the thrashing in the cases where multilevel nested loop contains multiple write accesses are given.