集群动态负载平衡系统的性能评价

该文使用随机Petri网对集群动态负载平衡系统建立了一个抽象模型．通过细化模型中的节点本地处理部分对5种动态负载平衡算法的性能进行了分析，并讨论了集群负载特性对动态负载平衡系统性能的影响，最后得出的主要结论有：(1)动态负载平衡算法可以取得比静态负载平衡算法更好的性能；(2)与传统的只考虑CPU就绪队列的负载平衡算法相比，考虑了各种I／O请求队列的负载平衡算法可以取得更好的性能；(3)即使在极端的集群负载特性中。集群动态负载平衡算法仍然能取得比较理想的性能，因此实现即使是十分简单的集群动态负载平衡系统也是很有必要的。

Performance Evaluation of Dynamic Load Balancing System for Clusters

A cluster system consists of a collection of computing nodes that share resources. Cluster systems utilize load balancing technology to share processing power and other resources, and thus to improve system performance, by transparently transferring load between nodes. In this paper, the Stochastic Petri Nets are employed to model the dynamic load balancing systems for clusters. The model we represent can avoid the disadvantages such as the lack of flexibility and the obvious difference from practical systems of previous work. We detailed the local process part of the model in order to analyze the performance of five dynamic load balancing schemes. We also discussed the impact of some workload characters of clusters on the performance of dynamic load balancing systems. It is found that:(1) Dynamic load balancing has the better system performance over that obtained with static load balancing;(2) Compared to the traditional load balancing algorithms that consider only the running queue, the load balancing algorithms which consider the I/O request queue can get better performance;(3) Even with extreme workload characters, the dynamic load balancing system can also get ideal performance, therefore implementing even a very simply dynamic load balancing system is also necessary.