Disclosed is an optical fiber mirror fabricated using an assistant rod bonded to an optical fiber and adapted to increase the cross-sectional area of a metal coating formed on the optical fiber at an end portion of the optical fiber, and a method for fabricating the optical fiber mirror. An inflator is provided in the low-pressure chamber with a gas discharge section facing the high-pressure chamber. The method also includes for each of a plurality of datacenters, determining an amount of electricity required to execute the application at the respective datacenter.