EDATA: Energy Debugging And Testing for Android

Abstract

This thesis was written in during my internship at Adyen as the final project of the Master’s program in Computer Science at the TU Delft. In my Bachelor’s thesis, I compared the energy consumption of three Android UI frameworks, and I chose to continue working on the subject of energy consumption on Android as it is relevant both to Adyen and the greater Android community. In this thesis, I review the state-of-the-art of energy consumption tools for Android, compare three approaches to attributing energy consumption to code at a fine-grained level, and implement one of these in a tool that can be used to analyze release-mode Android apps. I then empirically evaluate this tool, and apply it at Adyen in a case study in which I cooperate with a developer to solve an energy bug. As part of the empirical evaluation, I also perform a preliminary comparison of release and debug mode with respect to energy consumption, using three code smells identified in prior work as having an effect on the energy use of methods containing them. The results of the empirical investigation show that statistical sampling can be applied to Android devices to attribute energy consumption to methods within a reasonable margin of error. It further shows that this approach can be used to identify differences in energy consumption between different versions of software. The comparison between release and debug mode showed that the overhead caused by the use of debug mode is not consistent, and varies between both different code smells and different devices. This has significant implications for further work measuring energy consumption on Android, as it implies that results obtained using debug mode cannot be generalized to release mode, which all apps will use in production environments. Finally, the case study showed that this approach is able to significantly assist the energy debugging process, and revealed that even today, developers often lack the information necessary to make informed decisions over the energy consumption of their software. However, once this information is made available, both developers and stakeholders are willing to adapt their decision-making to incorporate energy efficiency.