EJB集群系统动态自适应负载均衡服务的设计与实现*

分析了几种常用的动态负载均衡算法的不足，并针对目前大多数主流J2EE应用服务器的负载均衡并不具有动态自适应性的问题，利用开源JBoss服务器为开发平台，结合多种设计模式设计了一种动态自适应负载均衡服务模型，具体实现细节围绕负载定义、负载收集以及均衡算法。提出了基于更新时间项的交替负载收集方式,并在此基础上实现了一种基于前K子集相对负载均衡度的动态自适应算法。测试结果表明该算法能较好地均衡系统的负载。

Design and implementation on self-adaptive dynamic load balance services in EJB cluster system

This paper presented the deficiencies of several common dynamic load balance algorithms and many of the main J2EE(Java 2 enterprise edition)application servers hadn't selfadaptive dynamic load balance.Using the Open Source JBoss as the developing platform and some of design pattems,this paper designed a model of self-adaptive dynamic load balance services.Centring on load indexes,load collection and balance algorithms,this paper came up with a new idea of alternating load collection based on update_time attribute,and realized a self-adaptive dynamic algorithm of relative load balance degree based on first K subset.The test results show this algorithm can balance the system loads betterly.