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arXiv · 2509.03855

Towards Deterministic Sub-0.5 us Response on Linux through Interrupt Isolation

Zhouyi Zhou·Zhili Liu·Shancong Zhang·Jiemin Li·Dengke Du·Mengke Sun·Zhiqiang Wang·Hongyan Liu·Guokai Xu
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Abstract

Real-time responsiveness in Linux is often constrained by interrupt contention and timer handling overhead, making it challenging to achieve sub-microsecond latency. This work introduces an interrupt isolation approach that centralizes and minimizes timer interrupt interference across CPU cores. By enabling a dedicated API to selectively invoke timer handling routines and suppress non-critical inter-processor interrupts, our design significantly reduces jitter and response latency. Experiments conducted on an ARM-based multicore platform demonstrate that the proposed mechanism consistently achieves sub-0.5 us response times, outperforming conventional Linux PREEMPT-RT configurations. These results highlight the potential of interrupt isolation as a lightweight and effective strategy for deterministic real-time workloads in general-purpose operating systems.

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Zhouyi Zhou, Zhili Liu, Shancong Zhang, Jiemin Li, Dengke Du, Mengke Sun, Zhiqiang Wang, Hongyan Liu, Guokai Xu. 2025-09-04. Towards Deterministic Sub-0.5 us Response on Linux through Interrupt Isolation. https://arxiv.org/abs/2509.03855

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