Most of today’s software systems are configurable, for example, we can set how long our operating system go to sleep, how many users a web server is going to support at the same time. Such software provides us different options to satisfy some requirements and performance attributes (i.e., objectives). However, a key problem here is that the relation between configuration options and performance attributes is not clear and unknown. So software configuration tuning (SCT), a problem of studying how to configure a system such that the best performance on some attribute can be achieved becomes an active topic.