Design And Implement Distributed Coordination Frmework Based On ZooKeeper

Distributed coordination is a very important problem in the design and implementation of distributed system. ZooKeeper is a powerful distributed coordination service, which can be used to solve many distributed coordination problem. ZooKeeper provides a very powerful API, which can be used to implement distributed coordination primitives. But ZooKeeper doesn’t provide distributed coordination directly.Based on in depth analysis of ZooKeeper and Java concurrency framework, this paper proposes to design and implement a distributed coordination framework based on ZooKeeper. The API of this distributed coordination framework likes Java concurrency framework. This paper design and implement KeeperClient, an enhanced ZooKeeper client library, which overcomes ZooKeeper client library’s deficiencies in session state management and retry mechanism. KeeperClient provides automatic session state management, session state notification, retry mechanism. Based on the API of Java concurrency framework, this paper designs the API of the distributed coordination framework, which provides distributed mutually exclusive lock, distributed read write lock, distributed barrier, distributed atomic variable, distributed leader election, etc. This paper also provides implementation of all the distributed coordination primitives in distributed coordination framework. The distributed coordination framework of this paper encapsulates the complex of ZooKeeper, provides an easy to use API.This paper also gives an example of using the distributed coordination framework. Distributed process can use distributed mutually exclusive lock or distributed atomic to generate distributed sequence ID. This example proves that distributed coordination framework is easy to use.