对等网维护数据副本一致性的乐观复制技术研究

Research of Optimistic Replication in Distributed Peer-to-Peer Environment

在对等网环境中,保持数据对象的多个副本可极大地提高数据的可靠性和访问效率,但同时需要维护副本数据的一致性。乐观复制在保证数据一致性的同时放松了对操作顺序的要求。提出了数据乐观复制系统形式化模型,应用模型推导了数据达到一致的基本条件,提出了一种基于处理操作的最优化算法,并对实际应用中可能出现的问题提出了改进方法。

In distributed peer-to-peer environment, the replica of data object can be used to improve availability and performance. To guarantee consistency, update conflicts that arise in such a system must be detected and resolved. Optimistic replication is a way to preserve consistency and relax the constraints on ordering. This paper proposes a formal model. And applying this model, it proposes the basic condition that guarantee consistency, proposes an algorithm that should be optimization in order to guarantee consistency, and extends the model to make it more suitable for real environment.