Content-based Workload-aware Request Distribution Policies in Cluster-based Web Servers

Abstract

How to efficiently dispatch requests from clients to web servers and effectively utilize system resource are crucial to the performance of a web cluster. In this paper, we have proposed new Content-based Workload-aware Request Distribution (CWARD) policies on cluster-based web servers. These policies take into account content in requests, workload information, and web object characterization in dispatching requests. Basically, the more frequently web objects are accessed, the more servers will serve the requests for these web objects. The experimental results of practical implementation on Linux show that our proposed Content-based Workload-aware Request Distribution policies are efficient. The trace-driven benchmarking with real-world traces of ClarkNet and WorldCup98 demonstrates that our proposed CWARD policies can effectively improve web cluster performance. Especially, when using the proposed CWARD policies, web clusters with content-aware dispatching such as LVS-CAD and LVS-CAD/FC can achieve up to 94% better performance than the Linux Virtual Server (LVS) web cluster with content-blind dispatching.