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

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.