ABSTRACT
In certain systems, e.g. sensor networks or batteryconstrained devices, energy consumption always plays a key design factor. Recent years, it has also become a major concern for other systems, including supercomputers, data centers and large-scale wired computing resources [1]. Take this in mind, there are several works, hardware-or softwarebased, proposed to tackle the sustainable problem, such as dynamic voltage & frequency scaling, caching solutions, power station located and workload oriented optimization. Nevertheless, before we run into any specific mechanism, we must firstly answer the question: how much energy does one particular server, disk, switching device or even the air conditioner consume in a given period?
