Mobile Web and Intelligent Information Systems

The autonomy of mobile devices is a requirement of utmost importance for end users. The autonomy is strongly related to the capacity of the built-in battery, in combination with the technical capabilities and the demand of energy of the diverse components of the device. As mobile equipment becomes more powerful and demanding, the need to find ways to optimize the overall energy consumption of the system grows as a critical research path. Software, as an instrumental component of a mobile system, is also an attractive target to deploy energy saving approaches. Several techniques of software-based energy aware strategies have been explored, including solutions placed at operating system, compiler and application level. In this paper, we present an energy saving strategy at operating system level. Our approach is implemented in the form of kernel extensions that assess the status of the device, and enable economic profiles without user intervention. Our experiments show that the power management kernel extension is able to significantly extend the battery runtime by 70 % to 75 %, at the expense of impacting user experience with an estimated performance degradation of 20% to 30 %.