Circuits and methods are provided for a reliability, availability and serviceability (RAS) enabled and self-regulated frequency and delay sensor of a semiconductor. A circuit for measuring and compensating for time-dependent performance degradation of an integrated circuit, includes at least one critical functional path of the integrated circuit, and Wearout Isolation Registers (WIR's) connected to boundaries of the critical functional path. The circuit also includes a feedback path connected to the WIR's, and a sensor control module operable to disconnect the critical functional path from preceding and succeeding functional paths of the integrated circuit, connect the critical functional path to the feedback path to form a critical path ring oscillator (CPRO), and enable the CPRO to generate an operating signal. A delay sensor module is operable to measure a frequency of the operating signal to determine and compensate for a degradation of application performance over a lifetime of a semiconductor product.