Performance And Portability In Parallel Computing: A Weather Forecast View

. We have developed a high level library, the Nearest Neighbor Tool (NNT), to facilitate the coding of finite difference approximation weather prediction models on parallel computers. NNT provides portability and ease of programming and at the same time optimizes performance by allowing the overlap of computation and communication to tolerate the latency of remote data moves. In this paper we describe NNT and the implementation of the Well Posed Topographic model (WPT), a finite difference approximation weather prediction model. We present a qualitative study of the performance of the code on various multiprocessors and evaluate the effectiveness of NNT. 1. Introduction Distributed memory multiprocessors with local address space are commonly used for high speed computing. In these machines data is shared among processors by sending and receiving messages containing that data. This movement of data is controlled explicitly by the programmer via send and receive instructions. The fact t..