Improving the energy efficiency of software systems for multi-core architectures

The ICT has an huge impact on the world CO2 emissions and recent study estimates its account to 2% of these emissions. This growing account emissions makes IT energy efficiency an important challenge. State-of-the-art has proven that the processor is the main power consumer. Processor are nowadays more and more complex and they are used in many hardware systems, such as computers or smartphones. This thesis is thus focusing on the software energy efficiency for multi-core systems. In this paper, we therefore report our motivations to understand deeply their architectures for improving their energy efficiencies. Manufacturers have worked tremendously to improve performance and reduce power consumption of their processors. However a lot of things remains to do in the software side. We claim that energy-efficient softwares can play a deterministic role to reduce the IT carbon footprint. To answer this challenge, we are believing on the software-metric approach with a minimal hardware investment. For this purpose, an efficient, scalable and non-invasive tool is needed. As a result, we created PowerAPI, to provide fine-grained power estimations at process and code-level for optimizing the software enegergy efficiency automatically. This solution will help to identify clearly the energy leaks for optimizing automatically the power consumed by software.