NSF-CGP Fellowship: Performance Studies of the EM-X Distributed-Memory Multiprocessor

9722187 Sohn本奖项为新泽西理工学院计算机与信息科学系Andrew Sohn博士与日本筑波电工实验室计算机科学部Yoshinori Yamaguchi博士的两次为期9个月的研究访问提供资金支持。他们的研究涉及开发算法，以调查何时、何地以及如何使用多线程和多线程体系结构来减少高性能计算机中并行处理器之间的通信时间。为了实现他们的目标，合作者有一项技术计划，包括以下五步：(1)针对选定的基准问题设计单线程和多线程的算法；(2)制定不同线程粒度的数据和工作负载分配策略；(3)实施算法来比较三种多处理器，即多线程EM-X(由日本电工实验室设计和建造)、单线程IBM SP-2和Cray T3E的性能；(4)分析表征单线程和多线程机器性能的参数；以及(5)建立一个模型来预测单线程和多线程所达到的性能。这项研究的主要结果将是一套工具和方法，能够识别多线程和多线程并行机与单线程机器的性能。这套工具和方法将帮助算法设计人员将单线程算法转换为多线程版本。这一结果还将帮助未来的超级计算机架构师开发多线程机器，以减少高性能计算的通信时间。孙正义和他的日本合作者在这一研究领域备受推崇。该项目由国家科学基金会和日本基金会全球伙伴关系中心之间的科学奖学金计划提供支持。***

9722187 Sohn This award provides funds to support two research visits, for a total of nine months, by Dr. Andrew Sohn, Department of Computer and Information Science, New Jersey Institute of Technology, for collaboration with Dr. Yoshinori Yamaguchi, Computer Science Division, Electrotechnical Laboratory, Tsukuba, Japan. Their research is concerned with developing algorithms to investigate when, where, and how multithreading and multithreaded architecture can reduce communication time between parallel processors in high performance computers. To achieve their objectives, the collaborators have a technical plan consisting of the following five steps: (1) design single-threaded and multithreaded algorithms for selected benchmark problems; (2) develop data and workload distribution strategies with varying thread granularity; (3) implement the algorithms to compare the performance of three multiprocessors, the multithreaded EM-X (designed and built by the Electrotechnical Laboratory, Japan), and the single-thread IBM SP-2, and Cray T3E; (4) analyze parameters that characterize the performance of single-threaded and multithreaded machines; and (5) formulate a model to predict the performance achieved by single threading and multithreading. The principle result of this research will be a set of tools and methodologies which enable the identification of the performance of multithreading and multithreaded parallel machines against single-threaded machines. This set of tools and methodologies will help algorithm designers to convert single-threaded algorithms to a multithreaded version. The results also will help future supercomputer architects develop multithreaded machines for reducing communication time towards high performance computing. The Dr. Sohn and his Japanese collaborator are highly regarded investigators in this field of research. This project is supported under the Science Fellowship Program between the National Science Foundation and the Japan Foundation Center for Global Partnership. ***