Database engines: evolution of greenness

Information Technology uses up to 10% of the world’s electricity generation, contributing to CO2 emissions and high energy costs. Data centers consume up to 23% of this energy, and a large fraction of this energy is consumed by databases. Therefore, building an energy efficient (green) database engine will reduce associated energy consumption and CO2 emissions. To understand the factors driving database energy consumption and execution time over the course of their evolution, we conducted an empirical case study of energy consumption of two MySQL database engines, InnoDB and MyISAM, across 12 releases. Moreover, we examined the relation between four software metrics and energy consumption & execution time, to determine the software metrics affecting the greenness and performance of a database. Our analysis shows that database engines energy consumption and execution time increase as databases evolve. Moreover, the Lines of Code metric is strongly correlated with energy consumption and execution time.