Redundant Execution Algorithm for Reducing Total Power Consumption of Server Clusters by Differentiating the Starting Time of Processes

In order to realize reliable and energy-aware server clusters, application processes have to be reliably and energy-efficiently performed in presence of server faults. In one way, an application process can be redundantly performed on multiple servers. In the improved redundant power consumption laxity-based (IRPCLB) algorithm which is proposed in our previous studies, since each application process is redundantly performed on more than one server, the reliability and availability of the cluster increase. However, the larger amount of electric power is consumed than non-redundant execution. In the IRPCLB algorithm, once a process terminates on a server, meaningless redundant processes on the other servers are forced to terminate in order to reduce the total power consumption. In this paper, we newly discuss the extended IRPCLB (EIRPCLB) algorithm to furthermore reduce the total power consumption of a server cluster. Here, in addition to forcing meaningless processes to terminate, each server is made reduce the consumption of computation resource to perform a redundant process by differentiating starting time of each redundant process. We evaluate the EIRPCLB algorithm in terms of total power consumption of a cluster and the average response time and number of servers to perform each process compared with the IRPCLB algorithm.