A performance comparison of homeless and home-based lazy release consistency protocols in software shared memory

In this paper, we compare the performance of two multiple-writer protocols based on lazy release consistency. In particular, we compare the performance of Princeton's home-based protocol and TreadMarks' protocol on a 32-processor platform. We found that the performance difference between the two protocols was less than 4% for four out of seven applications. For the three applications on which performance differed by more than 4%, the TreadMarks protocol performed better for two because most of their data were migratory, while the home-based protocol performed better for one. For this one application, the explicit control over the location of data provided by the home-based protocol resulted in a better distribution of communication load across the processors. These results differ from those of a previous comparison of the two protocols. We attribute this difference to (1) a different ratio of memory to network bandwidth on our platform and (2) lazy diffing and request overlapping, two optimizations used by TreadMarks that were not used in the previous study.

在本文中，我们比较了两种基于懒惰释放一致性的多写协议的性能。特别是，我们在一个32处理器平台上比较了普林斯顿的基于归属的协议和TreadMarks协议的性能。我们发现，对于七个应用中的四个，这两种协议之间的性能差异小于4%。对于性能差异超过4%的三个应用，TreadMarks协议在两个应用中表现更好，因为它们的大部分数据是迁移性的，而基于归属的协议在一个应用中表现更好。对于这一个应用，基于归属的协议对数据位置的显式控制导致了处理器间通信负载的更好分布。这些结果与之前对这两种协议的比较结果不同。我们将这种差异归因于（1）我们平台上内存与网络带宽的不同比率，以及（2）懒惰差异计算和请求重叠，这是TreadMarks使用的两种优化，而在之前的研究中未被使用。