LiME: The Linux Real-Time Task Model Extractor

We present LIME, a novel dynamic real-time task model extractor. LIME observes the temporal behavior of Linux real-time threads and automatically maps the observed activity to established real-time task models: sporadic and periodic tasks, upper and lower arrival curves, cumulative execution-time curves, and two self-suspension models (dynamic and segmented). LIME runs on unmodified Linux kernels and requires neither knowledge of real-time theory nor familiarity with Linux internals to be used effectively. An extensive evaluation shows LIME to achieve very high inference accuracy—in particular 100% accuracy for common automotive periods—with low kernel overhead, low latency impact, and low processor utilization (at best-effort priority).