分布式系统动态配置技术的研究与实现

动态配置技术用于系统运行时刻改变系统配置,从而满足分布式系统对在线演化的需求。如何保证系统一致性,并尽可能提高动态配置性能,是动态配置研究需要解决的关键问题。本文提出了行为一致性,并将系统一致性总结为行为一致性、构件状态一致性、应用状态一致性和引用一致性。通过扩展静止状态理论,本文提出了采用等待方式和阻塞方式驱动构件进入静止状态的算法,保证了行为一致性。通过分析动态配置意图,本文提出了保证系统一致性的动态配置算法,确定了采用等待方式和阻塞方式的动态配置场景,从而在严格保证行为一致性的前提下,尽可能地提高了动态配置性能。最后,本文基于 CCM 构件平台实现了动态配置平台。性能测试的结果表明,该平台可满足应用对性能的要求。

Research and Implementation of Dynamic Reconfiguration Technology in Distributed System

Dynamic reconfiguration aims to evolve distributed systems online by changing systems' configurations at runtime.How to preserve system consistency and to improve reconfiguration performance are the key issues in the re- search of dynamic reconfiguration.The paper presents behavioral consistency and summarizes the system consistency as:behavioral consistency,component state consistency,application state consistency and reference consistency.By extending the quiescent state theory,the paper proposes algorithms to drive component into quiescent state in waiting or holding mode so that the behavioral consistency is preserved.Based on the analysis of reconfiguration intentions and by choosing proper mode to drive component into quiescent state,the paper presents reconfiguration algorithms which improve reconfiguration performance as much as possible with the precondition that system consistency is preserved strictly.Finally,the paper implements the reconfiguration platform based on CCM,which is proven to meet the per- formance requirement of applications through the performance test.