A generalized model for investigating scheduling schemes in computational clusters

•A generalized model is proposed for computational clusters.•Parameters according to the SPECpower_ssj2008 benchmark are used in a model.•A method to rank physical servers is provided.•Three schemes for buffering jobs in a computational cluster are investigated.

In this paper, we present a generalized model for the performance evaluation of scheduling compute-intensive jobs with unknown service times in computational clusters. We propose the application of parameters defined in the SPECpower_ssj2008 benchmark of the Standard Performance Evaluation Corporation to construct a performance evaluation model. In addition, we also define a method to rank physical servers based on either the high performance priority or the energy efficiency priority, and measures to characterize the performance of computational clusters.We investigate three schemes (separate queue, class queue and common queue) for buffering jobs in a computational cluster that is built from Commercial Off-The-Shelf (COTS) servers. Numerical results show that the buffering schemes do not have impact on performance measures related to the energy consumption of the investigated cluster. However, the buffering schemes play an important role in ensuring the quality of service parameters such as the waiting time and the response time experienced by arriving jobs. Furthermore, Dynamic Voltage and Frequency Scaling should be carefully applied to reduce the energy consumption of computational clusters.