We have developed a system architecture, measuring and modeling techniques, and algorithms for on-line power and energy optimization and thermal management. The starting point for our approach is a simple and small gate-level network that can be used for real-time and low overhead measurement of temperature on chip positions where our network gates are placed. We use linear programming and interpolation to calculate the temperature at any arbitrary point of the integrated circuit. The periodic calculations of the temperature are used to estimate locally dissipated energies, which are consequently used to derive the most efficient use of operational times to minimize the overall leakage energy. All concepts and algorithms are experimentally validated using a simulation platform that consists of the Alpha 21364 processor and the SPEC benchmarks. Categories and Subject Descriptors B.7.m [Hardware]: Integrated Circuits--Miscellaneous General Terms Measurement, Design Keywords Leakage Ener...