On the impact of energy-efficient strategies in HPC clusters

Energy-aware management strategies are a recent trend towards achieving energy-efficient computing in HPC clusters. One of the approaches behind those strategies is to apply energy-saving states on idle nodes, alternating them among different sleep states that reflect on many power consumption levels. This paper investigated the way such energy-efficient strategies affected the job turnaround time - the elapsed time between when the job is submitted and when the job is completed, including the wait time as well as the job's actual execution time - in these clusters. Based on the results we proposed a Best-Fit Energy-Aware Strategy that switches the nodes to a sleep state, depending on the throughput of the resource manager's job queue. We simulated the proposed strategy using the SimGrid simulator. Our preliminary results showed a reduction of up to 19% in the overall energy consumption and give us a better understanding of the trade-offs involved in using energy-efficient strategies.