After scheduling, memory management and resource allocation, the paper considers another application of the proposed design approach, namely that aimed at realising 'power awareness'. Such a capability is of particular relevance nowadays, since operating systems run on a variety of devices that are not designed for a single purpose, but rather host different applications, each with its own requirements. In this context, an incorrect use of the functionalities made available by the host architecture could easily result in an undue power consumption, or even in the inability of satisfying the applications' needs. In a battery-operated device the relevance of the mentioned problem is apparent, and also larger systems can be affected. In the former case the energies coming into play are small, and the main issue is battery life, in the latter the same energies are instead relevant, and the main concern is their cost. Given also the need for an operating system to scale on differently sized architectures, which is nowadays another important characteristic in a view to application portability and user experience uniformity, a unitary framework to cast the power awareness problem into, is thus highly desirable.

Chapter Contents:

• 9.1 A case study
• 9.1.1 Step 1: Analysis, sensors and actuators
• 9.1.2 Step 2a: Data collection
• 9.1.3 Step 2b: Control design
• 9.1.4 Step 3: Control structure parameterisation
• 9.2 Experimental results
• 9.3 Generalisation
• 9.3.1 Step 1
• 9.3.2 Step 2a
• 9.3.3 Step 2b
• 9.3.4 Step 3
• 9.4 Concluding remarks

Inspec keywords: power aware computing

Other keywords: memory management; unitary framework; battery life; resource allocation; design approach; application portability; user experience uniformity; scheduling; power awareness approach; operating systems

Subjects: Operating systems; Performance evaluation and testing