Thermal-Aware Power Budgeting and Transient Peak Computation for Dark Silicon Chip

System designers usually use TDP as power budget. However, using a single and constant value as power budget is a pessimistic approach for manycore systems.
Therefore, we proposed a new power budget concept, called Thermal Safe Power (TSP), which is an abstraction that provides safe power constraints as a function of the number of active cores. Executing cores at power values below TSP results in a higher system performance than state-of-the-art solutions, while the chip's temperature remains below the critical levels.

Furthermore, runtime decisions (task migration, power gating, DVFS, etc.) are typically used to optimize resource usages. Such decisions change the power consumption, which can result in transient temperatures much higher than steady-state scenarios. To be thermally safe, it is important to evaluate the transient peaks before making resource management decisions.
Hence, we developed a lightweight method for computing these transient peaks, called MatEx, based on analytically solving the system of thermal differential equations using matrix exponentials and linear algebra, instead of using regular numerical methods.

TSP and MatEx (available at http://ces.itec.kit.edu/download) are new steps towards dealing with dark silicon. TSP alleviates the pessimistic dark silicon estimations of TDP, and it enables new avenues for performance improvements. MatEx allows for lightweight transient and peak temperature computations useful to quickly predict the thermal behavior of runtime decisions.