基于对象中间件的自适应容错技术

Adaptive Fault Tolerance Technology Based on Object Middleware

一、引言近年来,计算机系统逐渐渗透到人类生活中的各个方面,对人类生活产生了不可估量的影响。目前,面向对象的分布式系统已经被广泛地应用于关键业系统中,如空中交通管制系统、在线支付系统和核电站控制系统等。显然,提供高可靠的服务是用户对系统最基本的要求,否则将造成重大财产,甚至人员损失。在过去的几十年间,针对分布式系统生命周期的不同阶段,研究人员提出了大量提高系统可靠性的方法。在分布式系统运行过程中,容错技术是保证分布式系统运行可靠性的重要手段。随着硬件可靠性的提高,软件设计错误成为系统的主要错误源,因此软件容错成为决定系统可靠性的极其重要的因素。目前,主要的软件容错模型包括版本复制、RB模型、NVP模型和NSCP模型。然而。

Distributed object-oriented systems are widely applied to mission-critical systems, such as real-time systems, online paying systems and stock exchange systems. Presently, main problem of business distributed object-oriented systems is how to integrate fault-tolerance service with system and still provide correct service for user at the event of system failure. In addition, distributed systems must always operate in highly dynamic environments, so fault tolerance mechanism should provide more intelligence to adapt itself to in response to the changes in system resource, application demands and user requirements. To solve these problems, adaptive fault-tolerance technology based on object middleware isadvanced. This paper analyzes main features of adaptive fault tolerance based on object middleware and its problems, evaluates representative systems, and introduces our present work. Finally we give future research direction.