Directly Related Quality Criteria and Metrics

Directly Related Quality Criteria and Metrics relate to quality properties known from standard quality models, but also introduce new aspects and a new quality property.

The property Efficiency considers aspects like runtime efficiency and usage of computer resources. Appropriate metrics to measure efficiency are CPU-intensity, memory usage, peripheral intensity and idleness. Runtime efficiency directly relates to the property Performance, as runtime efficient programs minimize energy consumption through less computer usage [2]. Hence, it is possible to define energy efficiency metrics for software [3], which relate the work done to the energy consumption of the IT system or components of it. By comparing the measured system with a reference system, it is possible to determine which system is more energy efficient [4].

An aspect newly introduced into the property Portability is hardware obsolescence. It considers the amount of hardware that must be replaced before it has reached the end of its useful lifetime in order to use the new soft-ware [1,3].

The property Feasibility [2] considers how the software engineering process follows and manages sustainability issues during its execution. Main aspects are carbon footprint [5], travel, energy, and waste [2], according to our life cycle of software products.