SPARS: A Reinforcement Learning-Enabled Simulator for Power Management in HPC Job Scheduling

TL;DR

SPARS is a flexible, reinforcement learning-enabled simulation platform for optimizing power management in HPC job scheduling, balancing energy efficiency with performance.

Contribution

It introduces a lightweight, modular simulator that integrates RL-based power management with traditional scheduling policies for HPC clusters.

Findings

Supports various scheduling policies including RL-enhanced variants.

Provides detailed metrics and visualizations for analysis.

Facilitates reproducible experiments and easy extension.

Abstract

High-performance computing (HPC) clusters consume enormous amounts of energy, with idle nodes as a major source of waste. Powering down unused nodes can mitigate this problem, but poorly timed transitions introduce long delays and reduce overall performance. To address this trade-off, we present SPARS, a reinforcement learning-enabled simulator for power management in HPC job scheduling. SPARS integrates job scheduling and node power state management within a discrete-event simulation framework. It supports traditional scheduling policies such as First Come First Served and EASY Backfilling, along with enhanced variants that employ reinforcement learning agents to dynamically decide when nodes should be powered on or off. Users can configure workloads and platforms in JSON format, specifying job arrivals, execution times, node power models, and transition delays. The simulator records comprehensive metrics-including energy usage, wasted power, job waiting times, and node utilization-and provides Gantt chart visualizations to analyze scheduling dynamics and power transitions. Unlike widely used Batsim-based frameworks that rely on heavy inter-process communication, SPARS provides lightweight event handling and consistent simulation results, making experiments easier to reproduce and extend. Its modular design allows new scheduling heuristics or learning algorithms to be integrated with minimal effort. By providing a flexible, reproducible, and extensible platform, SPARS enables researchers and practitioners to systematically evaluate power-aware scheduling strategies, explore the trade-offs between energy efficiency and performance, and accelerate the development of sustainable HPC operations.