Analysis of Factors Affecting Execution Performance of OpenMP Programs  

作　　者：李建江 舒继武 陈永健 王鼎兴 郑纬民 

机构地区：[1]Department of Computer Science and Technology, Tsinghua University, Beijing 100084, China

出　　处：《Tsinghua Science and Technology》2005年第3期304-308,共5页清华大学学报（自然科学版（英文版）

基　　金：Supported by the National Natural Science Foundation of China (No. 69933202) and by the Intel Corporation

摘　　要：OpenMP is able to develop multithreaded programs with lower cost as a promising way to quickly parallelize a great number of serial programs. However, there are many difficulties when developing OpenMP multithreaded programs. Most importantly, the performance of OpenMP programs cannot be guar- anteed, which has greatly affected the application of OpenMP. This paper examines several factors that af- fect the execution performance of OpenMP programs, including loop transformation, scheduling strategy, the number of threads, and nested parallelism. The results show that one of the key reasons for perform- ance degradation is load imbalance, which can be corrected by reasonable use of these key factors to im- prove the execution performance of OpenMP programs.OpenMP is able to develop multithreaded programs with lower cost as a promising way to quickly parallelize a great number of serial programs. However, there are many difficulties when developing OpenMP multithreaded programs. Most importantly, the performance of OpenMP programs cannot be guar- anteed, which has greatly affected the application of OpenMP. This paper examines several factors that af- fect the execution performance of OpenMP programs, including loop transformation, scheduling strategy, the number of threads, and nested parallelism. The results show that one of the key reasons for perform- ance degradation is load imbalance, which can be corrected by reasonable use of these key factors to im- prove the execution performance of OpenMP programs.

关 键 词：OPENMP loop transformation scheduling strategy nested parallelism number of threads load  imbalance 

分 类 号：TP301.6[自动化与计算机技术—计算机系统结构]