Model Predictive Control for Memory Profiling

We make two contributions in the area of memory profiling. The first is a real-time, memory-profiling toolkit we call Memcov that provides both allocation/deallocation and access profiles of a running program. Memcov requires no recompilation or relinking and significantly reduces the barrier to entry for new applications of memory profiling by providing a clean, non-invasive way to perform two major functions: processing of the stream of memory-allocation events in real time and monitoring of regions in order to receive notification the next time they are hit. Our second contribution is an adaptive memory profiler and leak detector called Memcov_MPC. Built on top of Memcov, Memcov_MPC uses model predictive control to derive an optimal control strategy for leak detection that maximizes the number of areas monitored for leaks, while minimizing the associated runtime overhead. When it observes that an area has not been accessed for a user-definable period of time, it reports it as a potential leak. Our approach requires neither mark-and-sweep leak detection nor static analysis, and reports a superset of the memory leaks actually occurring as the program runs. The set of leaks reported by Memcov_MPC can be made to approximate the actual set more closely by lengthening the threshold period.