Distributed Server Cluster Research Articles

Preliminary Research on Distributed Cluster Monitoring of G/S Model

In the G/S model, the distributed server cluster is responsible for providing spatial data management and information sharing. Monitoring is the main task of cluster management. This paper studied the implementation of current cluster monitoring systems and on this basis proposed solutions of G/S cluster monitoring, mainly make a new exploration on the storage of monitoring data – the monitoring information is stored in HGML files, and around the storage model achieved other functions the monitoring system needed, finally the prototype system was developed and the strategy was verified.

A distributed admission control model for QoS assurance in large-scale media delivery systems

Conventional admission control models incur some performance penalty. First, admission control computation can overload a server that is already heavily loaded. Also, in large-scale media systems with geographically distributed server clusters, performing admission control on each cluster can result in long response latency, if the client request is denied at one site and has to be forwarded to another site. Furthermore, in prefix caching, initial frames cached at the proxy are delivered to the client before the admission decisions are made. If the media server is heavily loaded and, finally, has to deny the client request, forwarding a large number of initial frames is a waste of critical network resources. In this paper, a novel distributed admission control model is presented. We make use of proxy servers to perform the admission control tasks. Each proxy hosts an agent to coordinate the effort. Agents reserve media server's disk bandwidth and make admission decisions autonomously based on the allocated disk bandwidth. We develop an effective game theoretic framework to achieve fairness in the bandwidth allocation among the agents. To improve the overall bandwidth utilization, we also consider an aggressive admission control policy where each agent may admit more requests than its allocated bandwidth allows. The distributed admission control approach provides the solution to the stated problems incurred in conventional admission control models. Experimental studies show that our algorithms significantly reduce the response latency and the media server load.

Performance test and analysis for an adaptive load balancing mechanism on distributed server cluster systems

As the next generation of Internet services requires more highly scalable and available server systems, the cost-effective cluster of a large number of distributed computers becomes a popular solution. In this paper, we investigate to design and develop a server load balancing mechanism on cluster architecture, called the ALBM cluster. In order to construct the more scalable and reliable Internet service system, the ALBM cluster system consists of independent but co-operable components. The ALBM cluster system supports adaptive load balancing among servers via its adaptive load balancer (ALB) component in Layer 4 level and Layer 7 level. The Management Station (M-Station) and the Administrator Console are in charge of cluster management, system configuration management, and performance counter management. The Node Service is a system-level agent that is deployed into a server node. The node management and cluster management are the major tasks of the agent. Beside, the ALBM cluster is a flexible open system whose features of functionality can change or be easily expanded without affecting the rest of the system. In this paper, we also present a set of our experimental results to compare the performance of the ALBM cluster with that of LVS scheduling cluster system. We compare performance results of the ALBM with RR, LC, and WLC scheduling algorithms of a LVS cluster in both of homogeneous and heterogeneous system environments.

On the Design, Development, Deployment, and Network Survivability Analysis of the Dynamic Routing System Protocol

With the ever-increasing demands on server applications, reliability is of paramount importance. Often these services are implemented using a distributed server cluster architecture where many servers act together providing end user services. We evaluated one hundred deployed systems and found that over a one-year period, thirteen percent of the hardware failures were network related. To reliably provide end-user services, the server clusters must guarantee server-to-server communication in the presence of these network failures. We describe a protocol designed to provide proactive dynamic routing for server clusters architectures called the Dynamic Routing System (DRS) protocol and present analysis to its survivability in the presence of network failure. Our experiments show that, for an eight-node server cluster with three concurrent network failures, the DRS provides a 267% improvement in the probability of server to server communication over a traditional network topology. Additionally, the proactive routing approach of the DRS performs better than traditional routing systems by fixing network problems before they affect application communication.