Event-Driven Energy Accounting for Dynamic Thermal Management

Event-Driven Energy Accounting for Dynamic Thermal Management

Frank Bellosa, Simon Kellner, Andreas Weissel

english July 30, 2003

TR-I4-03-02

[Abstract] [Full Paper (ps,http) , 1 MB] [Full Paper (pdf) , 649 kB]

Abstract: With increasing clock speed and level of integration in today's processors, memories, and I/O-controllers, power dissipation is becoming a definitive concern of system design. Control-theoretic techniques have proven to manage the heat dissipation and temperature starting from the level of functional blocks within the processor up to the level of complete systems, so that a thermal emergency will never be reached. However application-, user- or service-specific requirements had to be neglected. In this work we investigate dynamic thermal management with respect to the demands of individual applications, users or services. We present an event-driven approach to determine on-the-fly the energy consumption on a fine grained level and describe a model to estimate the temperature without the need for measurement. With this power and thermal model-combined with the well-known facility of resource containers-it is possible to throttle the execution of individual tasks according to their energy-specific characteristics and the thermal requirements of the system. In addition to throttling we investigate a modified process scheduler which allots CPU time according to the power contribution of each task to the current temperature level of the processor. Experiments using a Pentium 4 architecture running a modified Linux show that a given temperature limit for the CPU will not be exceeded while tasks are scheduled according to their energy consumption.