GreenSlot

TLDR

The paper proposes GreenSlot, a parallel batch job scheduler that balances photovoltaic solar power and grid backup for datacenter workloads. GreenSlot predicts near‑future solar output and schedules jobs to maximize green energy use, resorting to cheap grid power only when deadlines would otherwise be missed. Experiments on production scientific workloads show GreenSlot can raise green energy usage by up to 117% and cut energy costs by up to 39%, demonstrating the potential of green‑energy‑aware scheduling for sustainable IT.

Abstract

In this paper, we propose GreenSlot, a parallel batch job scheduler for a datacenter powered by a photovoltaic solar array and the electrical grid (as a backup). GreenSlot predicts the amount of solar energy that will be available in the near future, and schedules the workload to maximize the green energy consumption while meeting the jobs' deadlines. If grid energy must be used to avoid deadline violations, the scheduler selects times when it is cheap. Our results for production scientific workloads demonstrate that Green-Slot can increase green energy consumption by up to 117% and decrease energy cost by up to 39%, compared to a conventional scheduler. Based on these positive results, we conclude that green datacenters and green-energy-aware scheduling can have a significant role in building a more sustainable IT ecosystem.