【作者】 李卫玲；

【导师】 李陶深；

【作者基本信息】 广西大学 ， 计算机应用技术， 2006， 硕士

【摘要】 分布式事务的提交和恢复机制是分布式数据库研究中的一个重要方面。提交协议负责事务的正确提交，恢复处理则是在事务处理系统发生故障后，使数据库恢复到某一个一致的状态，它们在维护事务的原子性和数据库的可靠性方面发挥着巨大作用。由于网格环境中资源的异构性、动态性、分布性等特点，已有的分布式事务提交和恢复机制不能完全适用于网格环境，因此，对网格环境下的事务提交和恢复机制的研究非常有意义。 本文所做的工作主要有： (1)分析网格环境下事务的特点，提出了一个基于Agent的网格事务模型。该模型利用Agent技术和网格中间件技术，能够适应网格环境下事务的长期性、动态性要求，支持参与者的自治性和彼此间的协作性，支持网格环境中资源的异构性。模型以基于服务的方式动态访问数据库，充分体现了网格的特点。网格中间件服务提供站点间的通信和协作。 (2)提出了一个面向网格的事务提交协议—Early no Prepare(ENP)protocol及相应的恢复处理方法。该协议取消了两阶段提交协议(2PC)中的投票阶段，参与者可以自行决定提交或终止，不必等待协调者发来的命令。设计了网格环境下的事务提交准则，对协议的正确性进行了证明，并对其进行了性能分析。通过理论分析表明，更多还原

【Abstract】 The research of transaction committing and recovery mechanism is an important aspect within the distributed database research. The committing protocol need ensure that the transaction can commit correctly. The recovery mechanism guarantee the consistency of database when failures occur.they cann’t be neglected in maintaining the atomity of transaction and dependency of database. The committing and recovery mechanism that we had cann’t solve the requirement of heterogeneity, distribution and dynamic characteristic in the grid environment. Therefore, it’s meaningful to study the transaction committing and recovery mechanism that oriented to the grid.The main content is as follows:First, this thesis analyzed the characteristicses of the transaction under grid environment, puts forward the transaction model which suits for grid environment------transaction model based on agent for grid. That model makes use of thetechnique of agent and grid-middleware, which adapt the longterm, dynamic characteristic request of transaction in grid environment, support the participant’s autonomy and cooperation, support the resources’s heterogeneity of grid environment at the same time. Model access the database with quomodo based service, embody the characteristics of grid fully. Grid middleware services provide communication and cooperation among stations.Second, this thesis puts forward the ENP(Early no Prepare) protocol and corresponding recovering mechanism facing to grid environment. ENP protocol cancel the vote phase of 2PC, and can decide to commit or abort by itself. That’s to say, it need not wait for the coordinator’s order. We design the committing rule, and proves the protocol’s correctness. We discuss its performance in theory, the analysis indicate that the ENP protocol lowered the message complexity and the log complexity of committing protocol, and the participant own the higher autonomy at the same time, which can satisfy participant the need of autonomy in grid environment .We do the experiment using Java, which validates the protocol’s更多还原