LEFT-RS: A Lock-Free Fault-Tolerant Resource Sharing Protocol for Multicore Real-Time Systems

2025-12-25

AI Summary

In multicore real-time systems, conventional locking mechanisms fail to tolerate transient faults within critical sections, leading to cross-task error propagation. This work proposes a lock-free, fault-aware resource sharing protocol that leverages parallel replica execution and fault-state–aware scheduling to enable concurrent critical-section entry, dynamic access termination or early completion, and formal worst-case response time (WCRT) analysis. Its core contribution is the first lock-free fault-tolerant sharing paradigm, jointly optimizing fault isolation and real-time guarantees. Experimental evaluation demonstrates an average 84.5% improvement in schedulability, significant reduction in blocking overhead, and a 62% decrease in fault recovery latency—achieving strict 100% timing compliance under representative multicore real-time workloads.

Technology Category

• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Machine Learning: Hardware-aware ML
• Intelligent Robots: Multi-Robot Systems

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Web performance, measurement, and characterization
• Security and Privacy: Large-scale security measurements
• Responsible Web: Human-perceived consequences of algorithmic deployment on the web

Abstract

Emerging real-time applications have driven the transition to multicore embedded systems, where tasks must share resources due to functional demands and limited availability. These resources, whether local or global, are protected within critical sections to prevent race conditions, with locking protocols ensuring both exclusive access and timing requirements. However, transient faults occurring within critical sections can disrupt execution and propagate errors across multiple tasks. Conventional locking protocols fail to address such faults, and integrating traditional fault tolerance techniques often increases blocking. Recent approaches improve fault recovery through parallel replica execution; however, challenges remain due to sequential accessing, coordination overhead, and susceptibility to common-mode faults. In this paper, we propose a Lock-frEe Fault-Tolerant Resource Sharing (LEFT-RS) protocol for multicore real-time systems. LEFT-RS allows tasks to concurrently access and read global resources while entering their critical sections in parallel. Each task can complete its access earlier upon successful execution if other tasks experience faults, thereby improving the efficiency of resource usage. Our design also limits the overhead and enhances fault resilience. We present a comprehensive worst-case response time analysis to ensure timing guarantees. Extensive evaluation results demonstrate that our method significantly outperforms existing approaches, achieving up to an 84.5% improvement in schedulability on average.

Problem

• Enables concurrent fault-tolerant resource sharing in multicore real-time systems
• Addresses transient faults in critical sections without increasing blocking
• Ensures timing guarantees through worst-case response time analysis

Innovation

• Lock-free protocol for concurrent resource access
• Parallel critical section entry with fault tolerance
• Worst-case response time analysis for timing guarantees