直接收集:一种简单有效的有限多写方法

在分析分布共享存储系统中假共享及多写算法对系统性能影响的基础上，提出了一种简单有效的有限多写方法－直接收集方法，ＤＣ方法兼收单写和多写算法的优点，实现了单写与多写的自动衔接，同时取消了通常多写方法中的Ｔｗｉｎ和Ｄｉｆｆ，简化了多写的实现。文中还给出了与传统的单写与多写方法的比较测试结果。

DIRECT COLLECTING: A SIMPLE WAY TO DEAL WITH FALSE SHARING IN DSMS

Single writer approach to false sharing in software DSM systems is simple but it can not avoid the ping pong effect of the date page thrashing, while multiple writer approach is effective to false sharing but the cost is high. This paper proposes a new approach called Direct Collecting (DC) to deal with false sharing in software DSMs. It distinguishes two kinds of false sharing in programs with lock based and barrier based forms, and handles them with single writer and multiple writer approaches respectively. It possibly discards the Twin and Diff in traditional multiple writer ways and simplifies the implementation of multiple writer in software DSM systems. The implementation of DC in CVM, which is a software DSM system based on a network of workstations, is introduced in this paper. Evaluating results show that for some applications such as SOR, FFT, and LU, DC provides a significant reduction in execution time (20% to 33%) compared to traditional multiple writer approach, and for matrix multiplication it can improve the performance compared to single writer approach by 36% on the platform.