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arXiv · 2610.08190

On the Impact of Degradation-Balanced Scheduling in Manycore Systems

Maria Pantazi-Kypraiou·George Goudroumanis·George Floros·Anuj Pathania·George Stamoulis
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Abstract

Electromigration degradation in manycore systems depends strongly on how runtime workload is distributed across cores. Task placement affects power, temperature, and current density, which in turn shape the spatial distribution of degradation over time. However, a scheduler that ranks cores only by their current reliability state may not always distinguish among candidate cores, especially when reliability values are close at decision time. In this case, scheduling decisions can be driven by secondary factors rather than by long-term degradation balance. This paper studies degradation-balanced scheduling and proposes a Reliability-Balanced (RB) policy that predicts the full-task effect of each candidate assignment. RB penalizes added imbalance in electromigration exposure, stress, active time, and task count while guarding the predicted Rvalue floor. On randomized continuous mixed workloads, the proposed scheduler preserves completed tasks while improving average Rvalue by 0.37% and minimum Rvalue by 4.35%. It reduces Rvalue, exposure, stress, and active-time standard deviation by 10.84%, 9.39%, 8.35%, and 16.38%, respectively.

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Maria Pantazi-Kypraiou, George Goudroumanis, George Floros, Anuj Pathania, George Stamoulis. 2026-10-06. On the Impact of Degradation-Balanced Scheduling in Manycore Systems. https://arxiv.org/abs/2610.08190

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