Dynamic service recovery in a grid environment
Grid computing is fast becoming a popular technology in both academic and business environment. The adoption of this technology into the business environment has been slow due to some challenges such as how to overcome low service availability. This challenge emanates from the dynamic nature of the Grid environment and the complexity of services. These two cause services to be fault-prone. Therefore, there is a need to develop an autonomic fault recovery mechanism that will effectively monitor, diagnose and recover a running service from failure. In addressing the above mentioned challenge, a dynamic service recovery model has been proposed. The model uses the replication approach to improve service availability whenever service failure is envisaged. The performance of the replication approach depends on how well a reliability index can be used to dynamically select two services of high reliability to serve an incoming service request. The service with higher reliability between the two selected services becomes the primary service while the other one becomes an active replica. An autonomic computing MAPE loop is implemented by the model to achieve runtime fault recovery. A simulation was carried out to evaluate the performance of the proposed model. The model was also compared with the existing active replication model. The results revealed that the newly proposed model exhibits superior performance characteristics especially when there are services with high and low reliability. It was also found that dynamic service recovery efficiency utilizes resource as a result of not-more-than two services serving a request.
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