Recently, operating systems have become increasingly multi-functional by the providing of various devices. Its functions are provided as driver programs. Even though average users do not use all functions, they do not customize and shrink their operating systems because of its job difficulty. Accordingly, they usually use wasteful and fat operating systems: much memory, slow down bootup time. In this paper, we propose an effective method for controlling invocation timing of device driver programs. As a strategy for the control, we use operation history on device drivers. And we present this design on AnT operating system.