关键词: 通信避免算法, 广义共轭余差法, 并行计算, 全球区域一体化数值预报模式, 曙光-派计算集群

Abstract: Generalized Conjugate Residual（GCR） method is an effective algorithm to solve asymmetrical linear systems. To reduce global communication of the algorithm, this paper puts forward the “communication avoiding generalized conjugate residual method”, avoids the global communication in the iterative process, global communication in the algorithm is reduced by an order of magnitude, at the same time reduces about 50% of the computation（the reduction of computation and communication related to scale）.In the massively experiment（the maximum process is 16 384）, the new algorithm is up to three times as fast as the original algorithm. Further analysis shows that：the new algorithm is faster and more scalable than the original algorithm in various parallel scales. In the case of small parallel scale, the advantages of the new algorithm mainly come from the reduction of computing. In the case of large parallel scale, the advantage of the new algorithm mainly comes from the reduction of global communication.

Key words: communication avoiding algorithm, generalized conjugate residual method, parallel computing, global/regional assimilation and prediction system, Sugon_&pi, cluster