Abstract
A DMVOCC-MVDA (distributed multiversion optimistic concurrency control with multiversion dynamic adjustment) protocol was presented to process mobile distributed real-time transaction in mobile broadcast environments. At the mobile hosts, all transactions perform local pre-validation. The local pre-validation process is carried out against the committed transactions at the server in the last broadcast cycle. Transactions that survive in local pre-validation must be submitted to the server for local final validation. The new protocol eliminates conflicts between mobile read-only and mobile update transactions, and resolves data conflicts flexibly by using multiversion dynamic adjustment of serialization order to avoid unnecessary restarts of transactions. Mobile read-only transactions can be committed with no-blocking, and respond time of mobile read-only transactions is greatly shortened. The tolerance of mobile transactions of disconnections from the broadcast channel is increased. In global validation mobile distributed transactions have to do check to ensure distributed serializability in all participants. The simulation results show that the new concurrency control protocol proposed offers better performance than other protocols in terms of miss rate, restart rate, commit rate. Under high work load (think time is 1s) the miss rate of DMVOCC-MVDA is only 14.6%, is significantly lower than that of other protocols. The restart rate of DMVOCC-MVDA is only 32.3%, showing that DMVOCC-MVDA can effectively reduce the restart rate of mobile transactions. And the commit rate of DMVOCC-MVDA is up to 61.2%, which is obviously higher than that of other protocols.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
LAM K Y, KUO T W, TSANG W H. Concurrency control in mobile distributed real-time database systems [J]. Information Systems, 2000, 25(4): 261–286.
LIAO Guo-qiong, LIU Yun-sheng, WANG Li-na. Concurrency control of real-time transactions with disconnections in mobile computing environment [C]// The 2003 International Conference on Computer Networks and Mobile Computing (ICCNMC03). Washington DC: IEEE Computer Society Press, 2003: 205–212.
LEE S K, KITSUREGAWA M, HWANG C S. Efficient processing of wireless read-only transactions in data broadcast [C]// The 12th International Workshop on Research Issues in Data Engineering: Engineering E-Commerce/E-Business Systems RIDE-2EC. Washington DC: IEEE Computer Society Press, 2002: 101–111.
LI Guo-hui, YANG Bing, CHEN Ji-xiong. Efficient optimistic concurrency control for mobile real-time transactions in a wireless data broadcast environment [C]// The 11th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications (RTCSA’05). Washington, DC: IEEE Computer Society Press, 2005: 443–446.
BRAVNER A, ALENCAR F S. A semantic-serializability based fully-distributed concurrency control mechanism for mobile multi-database systems [C]// The 16th International Workshop on Database and Expert Systems Applications (DEXA’05). Washington DC: IEEE Computer Society Press, 2005: 1085–1089.
LEI Xiang-dong, YUAN Xiao-li. Validation concurrency control protocol in parallel real-time database systems [J]. Journal of Central South University of Technology, 2002, 9(3): 198–201.
LEE V C S, LAM K W, SON S H. On transaction processing with partial validation and timestamp ordering in mobile broadcast environments [J]. IEEE Transactions on Computers, 2002, 51(10): 1196–1211.
LEE V C S, LAM K W, KUO T W. Efficient validation of mobile transactions in wireless environments [J]. The Journal of Systems and Software, 2004, 69(1): 183–193.
LEI Xiang-dong, ZHAO Yue-long, YUAN Xiao-li. Transaction processing in mobile database systems [J]. Chinese Journal of Electronics, 2005, 14(3): 491–494.
KUMAR V, PRABHU N, DUNHAM M H, SEYDIM A Y. TCOT-A timeout-based mobile transaction commitment protocol [J]. IEEE Transactions on Computers, 2002, 51(10): 1212–1218.
LINDSTRÖM J. Performance of distributed optimistic concurrency control in real-time databases [C]// The 17th International Conference on Information Technology (CIT 04). Berlin Heidelberg: Springer-Verlage, 2004, 3356: 243–252.
PARK C, PARK S, SON S H. Multiversion locking protocol with freezing for secure real-time database systems [J]. IEEE Transactions on Knowledge and Data Engineering, 2002, 5(14): 1141–1154.
DATA A, SON S H. Limitations of priority cognizance in conflict resolution for firm real-time database systems [J]. IEEE Transaction on Computers, 2000, 49(5): 483–501.
PITOURA E, CHRYSANTHIS P K. Multiversion data broadcast [J]. IEEE Transactions on Computers, 2002, 51(10): 1224–1230.
GUOHONG C. Proactive power-aware cache management for mobile computing systems [J]. IEEE Transactions on Computers, 2002, 51(6): 608–621.
Author information
Authors and Affiliations
Corresponding author
Additional information
Foundation item: Project(20030533011) supported by the National Research Foundation for the Doctoral Program of Higher Education of China
Rights and permissions
About this article
Cite this article
Lei, Xd., Zhao, Yl., Chen, Sq. et al. Scheduling transactions in mobile distributed real-time database systems. J. Cent. South Univ. Technol. 15, 545–551 (2008). https://doi.org/10.1007/s11771-008-0103-y
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11771-008-0103-y