syncchecker: detecting synchronization errors between mpi applications and libraries

ISCAS OpenIR

	syncchecker: detecting synchronization errors between mpi applications and libraries
	Chen Zhezhe; Li Xinyu; Chen Jau-Yuan; Zhong Hua; Qin Feng
	2012
会议名称	2012 IEEE 26th International Parallel and Distributed Processing Symposium, IPDPS 2012
会议录名称	Proceedings of the 2012 IEEE 26th International Parallel and Distributed Processing Symposium, IPDPS 2012
页码	342-353
会议日期	May 21, 2012 - May 25, 2012
会议地点	Shanghai, China
收录类别	EI
ISBN	9780769546759
部门归属	(1) Dept. of Computer Science and Engineering Ohio State University United States; (2) Technology Center of Software Engineering Institute of Software Chinese Academy of Sciences China
摘要	While improving the performance, nonblocking communication is prone to synchronization errors between MPI applications and the underlying MPI libraries. Such synchronization error occurs in the following way. After initiating nonblocking communication and performing overlapped computation, the MPI application reuses the message buffer before the MPI library completes the use of the same buffer, which may lead to sending out corrupted message data or reading undefined message data. This paper presents a new method called Sync Checker to detect synchronization errors in MPI nonblocking communication. To examine whether the use of message buffers is well synchronized between the MPI application and the MPI library, Sync Checker first tracks relevant memory accesses in the MPI application and corresponding message send/receive operations in the MPI library. Then it checks whether the correct execution order between the MPI application and the MPI library is enforced by the MPI completion check routines. If not, Sync Checker reports the error with diagnostic information. To reduce runtime overhead, we propose three dynamic optimizations. We have implemented a prototype of Sync Checker on Linux and evaluated it with seven bug cases, i.e., five introduced by the original developers and two injected, in four different MPI applications. Our experiments show that Sync Checker detects all the evaluated synchronization errors and provides helpful diagnostic information. Moreover, our experiments with seven NAS Parallel Benchmarks demonstrate that Sync Checker incurs moderate runtime overhead, 1.3-9.5 times with an average of 5.2 times, making it suitable for software testing. © 2012 IEEE.; While improving the performance, nonblocking communication is prone to synchronization errors between MPI applications and the underlying MPI libraries. Such synchronization error occurs in the following way. After initiating nonblocking communication and performing overlapped computation, the MPI application reuses the message buffer before the MPI library completes the use of the same buffer, which may lead to sending out corrupted message data or reading undefined message data. This paper presents a new method called Sync Checker to detect synchronization errors in MPI nonblocking communication. To examine whether the use of message buffers is well synchronized between the MPI application and the MPI library, Sync Checker first tracks relevant memory accesses in the MPI application and corresponding message send/receive operations in the MPI library. Then it checks whether the correct execution order between the MPI application and the MPI library is enforced by the MPI completion check routines. If not, Sync Checker reports the error with diagnostic information. To reduce runtime overhead, we propose three dynamic optimizations. We have implemented a prototype of Sync Checker on Linux and evaluated it with seven bug cases, i.e., five introduced by the original developers and two injected, in four different MPI applications. Our experiments show that Sync Checker detects all the evaluated synchronization errors and provides helpful diagnostic information. Moreover, our experiments with seven NAS Parallel Benchmarks demonstrate that Sync Checker incurs moderate runtime overhead, 1.3-9.5 times with an average of 5.2 times, making it suitable for software testing. © 2012 IEEE.
关键词	Communication Computer Operating Systems Distributed Parameter Networks Experiments Libraries Software Testing
语种	英语
内容类型	会议论文
URI标识	http://ir.iscas.ac.cn/handle/311060/15748
专题	中国科学院软件研究所
推荐引用方式 GB/T 7714	Chen Zhezhe,Li Xinyu,Chen Jau-Yuan,et al. syncchecker: detecting synchronization errors between mpi applications and libraries[C],2012:342-353.