A Real-Time Instruction Cache with High Average-Case Performance

Cache memories, while useful for improving the average-case performance for general-purpose applications, are not suitable for real-time systems due to the time unpredictability. In this paper, we propose a Performance Enhancement Guaranteed Cache (PEG-C) to ensure performance improvement in the worst case while achieving as good average-case performance as a regular hardware-controlled cache. We design and evaluate an instruction PEG-C as a proof-of-concept. Our experiments indicate that with a small number of preloaded instructions, the PEG instruction cache can achieve the same performanceas a regular instruction cache, and outperform cache locking significantly.