支持协作设计的工程数据库并发控制机制的研究
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摘要
随着Internet的飞速发展,协同设计系统从局域网环境扩展到广域网的环境。并发控制机制是数据库事务管理中非常重要的一部分,其性能的优劣是衡量一个数据库系统功能强弱和性能好坏的重要标志之一。本文主要开展了支持开放式协同设计的分布式工程数据库事务管理的并发控制机制的研究,取得了以下的研究成果:
(1)设计了适合于开放式协同工作环境的四层分布式工程数据库协同设计体系结构,该体系结构包括用户界面层、Web服务层、应用服务层、数据库服务层。其中,用户界面层用于为用户提供良好的接口;Web服务层负责将用户的请求用SOAP协议格式传给应用服务层;应用服务层完成对用户请求的处理和将结果传送给用户;数据库服务层用于存储协同设计的数据。
(2)在分析了协作环境下工程设计事务的特点和现有的分布式并发控制机制的不足基础上,提出一种适合于开放式协同工作环境的支持协同设计的并发控制算法——基于有序相容性多粒度的多版本两阶段锁协议,并对其正确性进行了证明。新协议将只读事务和更新事务区分开,只读事务在执行时遵守多版本时间戳排序协议,而更新事务的执行将按基于两阶段有序相容性封锁的多粒度封锁协议进行。该协议将只读事务与更新事务区分开,解决了只读事务和更新事务之
With the rapid development of Internet, the cooperative design system has extended from local-area network to wide-area network. Being a very important part in transaction management of database, the quality of concurrency control is one of the key criterions in evaluating the performance of a database system. This paper focuses on studying concurrency control mechanism of transaction management in distributed engineering database that supports open, cooperative design. The achievement is as follows:(1) An architecture of four-layer distributed engineering database fit for that environment is presented. The four layers are user interface layer, Web service layer, application service layer and database service layer. The function of each layer is as follows: user interface layer supplies users with friendly interfaces; Web service layer converts the user's request to application service layer by SOAP contract; application service layer deal with the user's request and then sends the results to them; database service layer stores data of cooperative design.(2) Based on the analysis of the features of cooperative design transaction in open environment and the disadvantages of the present distributed concurrency control protocol, a concurrency control protocol for cooperative design transaction in open environment is proposed. It is a multiversion two-phase lock protocol based on ordered sharing multi-granularity locks and its correctness is also tested. Under the new protocol, read-only transaction and update transaction is distinguished. The former abides the multiversion timestamp ordering protocol, while that of the latter follows the multi-granularity locking mechanism based on ordered sharing locks. Under the new protocol, the conflict between read-only transaction and update transaction can be resolved , the flexibility of transaction execution can be enhanced. That is, the new protocol is fit for the engineering database that supports cooperative design.(3) What's more, the executable algorithm of the multiversion two-phase lock protocol based on ordered sharing multi-granularity locks is also given. Based on the architecture of four-layer distributed engineering database in open environment that supports cooperative design, an experiment environment is constructed. Under such a environment, the experiment of the multiversion two-phase lock protocol based on ordered sharing multi-granularity locks is carried out and the performance of the new protocol is analyzed as well. That is, the new protocol is fit for that open environment.
(1)设计了适合于开放式协同工作环境的四层分布式工程数据库协同设计体系结构,该体系结构包括用户界面层、Web服务层、应用服务层、数据库服务层。其中,用户界面层用于为用户提供良好的接口;Web服务层负责将用户的请求用SOAP协议格式传给应用服务层;应用服务层完成对用户请求的处理和将结果传送给用户;数据库服务层用于存储协同设计的数据。
(2)在分析了协作环境下工程设计事务的特点和现有的分布式并发控制机制的不足基础上,提出一种适合于开放式协同工作环境的支持协同设计的并发控制算法——基于有序相容性多粒度的多版本两阶段锁协议,并对其正确性进行了证明。新协议将只读事务和更新事务区分开,只读事务在执行时遵守多版本时间戳排序协议,而更新事务的执行将按基于两阶段有序相容性封锁的多粒度封锁协议进行。该协议将只读事务与更新事务区分开,解决了只读事务和更新事务之
With the rapid development of Internet, the cooperative design system has extended from local-area network to wide-area network. Being a very important part in transaction management of database, the quality of concurrency control is one of the key criterions in evaluating the performance of a database system. This paper focuses on studying concurrency control mechanism of transaction management in distributed engineering database that supports open, cooperative design. The achievement is as follows:(1) An architecture of four-layer distributed engineering database fit for that environment is presented. The four layers are user interface layer, Web service layer, application service layer and database service layer. The function of each layer is as follows: user interface layer supplies users with friendly interfaces; Web service layer converts the user's request to application service layer by SOAP contract; application service layer deal with the user's request and then sends the results to them; database service layer stores data of cooperative design.(2) Based on the analysis of the features of cooperative design transaction in open environment and the disadvantages of the present distributed concurrency control protocol, a concurrency control protocol for cooperative design transaction in open environment is proposed. It is a multiversion two-phase lock protocol based on ordered sharing multi-granularity locks and its correctness is also tested. Under the new protocol, read-only transaction and update transaction is distinguished. The former abides the multiversion timestamp ordering protocol, while that of the latter follows the multi-granularity locking mechanism based on ordered sharing locks. Under the new protocol, the conflict between read-only transaction and update transaction can be resolved , the flexibility of transaction execution can be enhanced. That is, the new protocol is fit for the engineering database that supports cooperative design.(3) What's more, the executable algorithm of the multiversion two-phase lock protocol based on ordered sharing multi-granularity locks is also given. Based on the architecture of four-layer distributed engineering database in open environment that supports cooperative design, an experiment environment is constructed. Under such a environment, the experiment of the multiversion two-phase lock protocol based on ordered sharing multi-granularity locks is carried out and the performance of the new protocol is analyzed as well. That is, the new protocol is fit for that open environment.
引文
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[2] Barghouti N. S, Kaiser G.. E, Concurrency Conrtol in Advanced Database Application, Acm Computing Surveys, 1991, 23(3): 269～317.
[3] Henry F. Korth, On Long_Durative CAD Transaction, Information Science, 1988, 46(3): 73～107.
[4] 齐进,张家明,周伯鑫等,工程数据库中一种支持合作设计事务的并发控制机制,计算机研究与发展,1998,35(11):987～990.
[5] Charles S. Smith. Cybercut: A World Wide Web Based Design to Fabrication Tool. Journal of Manufacturing System, 1996, 15(6): 432—442.
[6] Wang. F. C, Wright. P. K. Intemet-based design and manufacturing on an open architecture machining center. Japan-USA Symposium on Flexible Automation, Ohtsu, Japan, 1998.
[7] Ahn S. H, Sequin C. S, Wright P K. Internet-based design and manufacturing. Final Report 1998-1999 for MICRO Project 98-136, University of California at Berkeley, 2000.
[8] Ahn. S. H, Roundy. S, Wright P K, et al. Design consultant: network-based concurrent design enterprise. Proc of the ASME 1999 Int Mechanical Engineering Congress & Exposition, Nashville, USA, 1999: 563～569.
[9] Y. V. Ramana Reddy. Computer Support for Concurrent Engineering Systems. IEEE Computer, 1993. Vol. 26(1): 12—16.
[10] Yan Jin. An Agent-Support Approach to Collaborative Design. Annals of the CIRP, 1998, 47(1): 107—110.
[11] Shi J, Huang G. Q, Mak K. L, Cyberagent: Collaborative agents for distributed applications over the Internet[A]. In: Proceedings of 2001 ASME Design Engineering Technical Conference[CD], Pittsburgh, Pennsylvania, 2001. DETC2001/DAC-21073.
[12] Michael P Case, Stephen C-Y Lu. Discourse Model for Collaborative Design. Computer Aided Design, 1996, 15(6): 333—345.
[13] Renate Fruchter. Conceptual Collaborative Building Design Through Shared Graphics. IEEE Expert, 1996, 11(3): 33—41.
[14] S. K. Tso, H. C. W. Lau, J. K. Ho, W. J. Zhang. A framework for developing an agent-based collaborative service-support system in a manufacture network. Engineering Applications of Artificial Intelligence, 1999, 12(1): 43—57.
[15] 林守勋,林宗楷,郭玉钗等,多Agent协同工作环境MACE,计算机学报,1998,21(2): 188—192.
[16] 史美林,杨光信,《CoDesign:一个协同设计系统原型》,清华大学学报,1998(SI):30—35.
[17] 章昊翰,潘志庚,石教英,基于多Agent模型的协同设计系统,软件学报,1998,9(增刊):98—102.
[18] 王魁生,李人厚,李宏敏等,一个CSCW系统的设计与实现,小型微型计算机系统,2001,22(2):214—218
[19] J. Munson and P. Dewan. A Concurrency Control Framework for Collaborative System. In Proceedings of ACM Conference on Computer Supported Cooperative Work. Cambridge, 1996, pp278-287.
[20] Joao Coelho Garcia, Paulo Ferreira, Concurrency Control for Distributed Cooperative Engineering Applications, ACM, 2002. Proceedings of the 2002 ACM symposium on Applied computing, Madrid, Spain, 958-963.
[21] Chanjung Park, Hwakyung Rim, A Locking-Based Transaction Scheduling Algorithm for Supporting Web-Based Classes, Springer-Verlag Berlin Heidelberg 2002, pp. 325-338.
[22] A. Climent, M. Bertran, F. Babot, Performance Analysis of Speculative Concurrency Control Algorithms based on Wait Depth Limited for Distributed Database Systems, Proceedings of the Second International Symposium on Parallel and Distributed Computing (ISPDC'03), IEEE, 2003
[23] Rashmi Srinivasa, Craig Williams, Paul F. Reynolds Jr., A New Look at Timestamp Ordering Concurrency Control, Springer-Verlag Berlin Heidelberg 2001, pp. 943-952.
[24] 杨光信,史美林,全复制结构下基于对象数据模型的并发控制模型,计算机学报,2000,23(2):101-114.
[25] Ellis C A, Gibbs S J, Concurrency control in groupware systems. In: Proceedings of ACM SIGMOD Conference on Management of Data, Seattle, 1989, 399-407.
[26] 宋海刚,陈学广,计算机支持的协同工作(CSCW)发展述评,计算机工程与应用,2004.1.
[27] 李陶深,廖国琼,支持工程合作设计事务的扩充分层封锁机制,计算机工程与应用,2002,38(7):47-49.
[28] Li Taoshen, Liao Guoqiong, Chen Guoning. Transaction Management Mechanisms in Distributed Engineering Database System. Proceeding of the Seventh Intemational Conference on Computer Aided Design and Computer Graphics, August22-24, 2001, Kunming, China. 785-790 (ISTP收录).
[29] 吴筱媛,顾宁,基于文档标注的并发控制方法,计算机研究与发展,2002.12,1662—1667.
[30] 郭学旭,王云鹏,潘翔等,计算机辅助协同设计系统并发控制机制的研究,计算机辅助设计与图形学学报,2004.2,201—205.
[31] Kvan T. Collaborative design: what is it?, AUTOMATION IN CONSTRUCTION, 2000, Vol. 9, No. 4: 409—415.
[32] 陆春进,张友良,王宏典,面向并行工程的协同CAD系统的初步研究,机械科学与技术,1998,17(6):1023—1025.
[33] 张志胜,史金飞,颜景平,基于Web的协同设计冲突消解系统研究,制造业自动化,2003.5.
[34] 童秉枢,现代CAD技术,清华大学出版社,1999.
[35] 付红桥,网络化协同设计的若干关键技术的研究及应用,重庆大学博士学位论文,2002.9.
[36] 王云鹏,雷毅,潘翔,郭学旭,基于Web Service的计算机辅助协同数据体系结构,计算机应用研究,2004.2:44—46.
[37] 贾焰,王志英,韩伟红等,分布式数据库技术,国防工业出版社,2000.7.
[38] 廖国琼,分布式工程数据库事务管理研究,硕士学位论文,广西大学,2000.6.
[39] 邵佩英编著,分布式数据库系统及其应用,科学出版社,2000.
[40] P.A.Bernstein, V.Hadzilacos and N. Goodman. Concurrency control and recovery in database system. Addison-Wesley Publishing Company. 1987.
[41] 陈国宁,支持协作设计的工程数据库事务管理的研究,硕士学位论文,广西大学,2001.6.
[42] 郑振楣,于戈,郭敏,分布式数据库,科学出版社,1998,7.
[43] Abraham Siberschatz, Henry F. Korth, S. Sudarshan.数据库系统概念,机械工业出版社,2003.3.
[44] Francois Llirbat, Eric Simon, Dinitri Tombroff. Using Version in Update Transactions: Application to Integrity Checking, INRIA 78153 Le Chesnay France, 1997. 3. 10.
[45] 齐进,工程数据库中支持合作过程的事务模型,博士学位论文,东南大学,1999.
[46] (美)Joseph Mayo著,王启丁,高锦文,刘明等译,C#技术内幕,机械工业出版社,2003.1.
[47] 黎晓冬,李华飚编著,精通C#编程,科学出版社,2003.1.
[48] 沉舟,崔培枝,何荣辉等编写,C#教程,北京希望电子出版社,2001.4.
[49] Gail E. Kaiser, Cooperative Transaction for Multi-User Environment, chapter 20 in Modern Database System: The Object Model, Interoperability and Beyond, edited by W. Kim, Addison-Wesley Publishing Company, 1995, p. 409-433.
[50] K. Aberer, S. Even, F. Faase, H. Kaijanranta, J. Klingemann, Transaction Support for Cooperative Work: An Overview of the TransCoop Project, Workshop on Extending Data Management for Cooperative Work, Darmstadt, June 6, 1997.
[51] SungHo Cho, Jeong-Hyon Hwang, Kyoung Yul Bae, Chong-Sun Hwang. Broadcast Invalidation Based Certification Protocol for Concurrency Control. ISIE 2001, Pusan, KOREA.
[52] Cristiana Amza, Alan L. Cox, Willy Zwaenepoel. Distributed Versioning: Consistent Replication for Scaling Back-End Databases of Dynamic Content Web Sites. M. Endler and D. Schmidt(Eds.): Middleware 2003, LNCS2672, PP. 282-304, 2003.
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