流场计算程序自动并行化的帧同步和帧通信策略

FRAME SYNCHRONIZATION AND COMMUNICATION STRATEGY IN AUTOMATIC PARALLELIZATION OF FLOWFIELD COMPUTATION

针对流场计算中巨大的计算量和存储量要求及并行机使用困难的问题，研究以ＳＰＭＤ模式把结构化网格有限差分算法的串行程序自动并行化后的同步和通信方法。提出了一种有效的帧同步和帧通信策略，在每帧结束时集中进行同步和通信。同时，设计了同步点自动定位算法，它是实现该策略的关键技术。通过分析，证明帧同步和帧通信策略能保证并行流场计算程序的正确性，有效降低同步和通信开销，并便于实现消息传递，从而获得了可观的加速比。

It is well known that parallel programming is quite difficult for common users. Considering the large requirement of computation and storage in flowfield computing, an efficient frame synchronization and communication strategy in automatic parallelization is presented. Serial programs of finite difference algorithm for structured grid can be automatically parallelized with SPMD mode. Synchronization and communication are put together at the end of each frame. An algorithm of automatically spotting the synchronization points is provided, which is a pivot in this strategy. This strategy is also beneficial in message passing scheme. A thorough study shows that the correctness of parallel flowfield computing can be assured, and the overhead of synchronization and communication is reduced considerably, so that an ideal speedup can be achieved.