Erik Jagroep

Software energy profiling: comparing releases of a software product

In the quest for energy efficiency of Information and Communication Technology, so far research has mostly focused on the role of hardware. However, as hardware technology becomes more sophisticated, the role of software becomes crucial. Recently, the impact of software on energy consumption has been acknowledged as significant by researchers in software engineering. In spite of that, measuring the energy consumption of software has proven to be a challenge, due to the large number of variables that need to be controlled to obtain reliable measurements. Due to cost and time constraints, many software product organizations are unable to effectively measure the energy consumption of software. This prevents them to be in control over the energy efficiency of their products. In this paper, we propose a software energy profiling method to reliably compare the energy consumed by a software product across different releases, from the perspective of a software organization. Our method allows to attribute differences in energy consumption to changes in the software. We validate our profiling method through an empirical experiment on two consecutive releases of a commercial software product. We demonstrate how the method can be applied by organizations and provide an analysis of the software related changes in energy consumption. Our results show that, despite a lack of precise measurements, energy consumption differences between releases of a software product can be quantified down to the level of individual processes. Additionally, the results provide insights on how specific software changes might affect energy consumption.

Profiling energy profilers

While energy is directly consumed by hardware, it is the software that provides the instructions to do so. Energy profilers provide a means to measure the energy consumption of software, enabling the user to take measures in making software more sustainable. Although each energy profiler has access to roughly the same data, the reported measurements can differ significantly between energy profilers. In this research, energy profilers are evaluated through a series of experiments on their functionality and the accuracy of the reported measurements. The results show that there is still work to be done before these software tools can be safely used for their intended purpose. As a start, a correction factor is suggested for the energy profilers.

Awakening awareness on energy consumption in software engineering

Software producing organizations have the ability to address the energy impact of their ICT solutions during the development process. However, while industry is convinced of the energy impact of hardware, the role of software has mostly been acknowledged by researchers in software engineering. Strengthened by the limited practical knowledge to reduce the energy consumption, organizations have less control over the energy impact of their products and lose the contribution of software towards energy related strategies. Consequently, industry risks not being able to meet customer requirements or even fulfillcorporate sustainability goals. In this paper we perform an exploratory case study on how to create and maintain awareness on an energy consumption perspective for software among stakeholders involved with the development of software products. During the study, we followed the development process of two commercial software products and provided direct feedback to the stakeholders on the effects of their development efforts, specifically concerning energy consumption and performance, using an energy dashboard. Multiple awareness measurements allowed us to keep track of changes over time on specific aspects affecting software development. Our results show that, despite a mixed sentiment towards the dashboard, changed awareness has triggered discussion on the energy consumption of software.

Energy efficiency on the product roadmap: an empirical study across releases of a software product

In the quest for energy efficient Information and Communication Technology, research has mostly focused on the role of hardware.

An Energy Consumption Perspective on Software Architecture

The rising energy consumption of the ICT industry has triggered a quest for more sustainable, i.e. energy efficient, ICT solutions. Software plays an essential role in finding these solutions, as software is identified as the true consumer of power. However, in this context, software is often treated as a single, complex entity which fails to provide detailed insight in the elements that invoke specific energy consumption behavior.

DevOps competences and maturity for software producing organizations

Software producing organizations aim to release high quality software faster, which triggers the adoption of DevOps. However, not many artifacts are available that aid in adopting DevOps. In an attempt to bridge this gap, a DevOps Competence Model showing an overview of the areas to be considered in adopting DevOps is proposed. Also, a DevOps Maturity Model is proposed that presents a growth path for software producing organizations. Both these models incorporate perspectives that are made up of focus areas which in turn are made up of capabilities. Apart from designing and validating these models by means of expert workshops, a case study has been conducted where assessees answered questions to gain insight into which capabilities were implemented. From the answers, maturity profiles were extracted that supported the assessees in becoming more DevOps mature.

The hunt for the guzzler: Architecture-based energy profiling using stubs

Abstract Context Software producing organizations have the ability to address the energy impact of their software products through their source code and software architecture. In spite of that, the focus often remains on hardware aspects, which limits the contribution of software towards energy efficient ICT solutions. Objective No methods exist to provide software architects information about the energy consumption of the different components in their software product. The objective of this paper is to bring software producing organizations in control of this qualitative aspect of their software. Method To achieve the objective, we developed the StEP Method to systematically investigate the effects of software units through the use of software stubs in relation to energy concerns. To evaluate the proposed method, an experiment involving three different versions of a commercial software product has been conducted. In the experiment, two versions of a software product were stubbed according to stakeholder concerns and stressed according to a test case, whilst energy consumption measurements were performed. The method provided guidance for the experiment and all activities were documented for future purposes. Results Comparing energy consumption differences across versions unraveled the energy consumption related to the products’ core functionality. Using the energy profile, stakeholders could identify the major energy consuming elements and prioritize software engineering efforts to maximize impact. Conclusions We introduce the StEP Method and demonstrate its applicability in an industrial setting. The method identified energy hotspots and thereby improved the control stakeholders have over the sustainability of a software product. Despite promising results, several concerns are identified that require further attention to improve the method. For instance, we recommend the investigation of software operation data to determine, and possibly automatically create, stubs.

Implementing software product portfolio management

In this paper, we present a research conducted on implementing product portfolio management (PPM) processes in software organizations. Based on interviews and literature study, we developed an implementation model intended for software companies aiming to implement PPM processes that span the entire organizational portfolio. The model presents a step by step implementation of the product portfolio management process and also takes into account related subjects. In addition, we present a maturity matrix that shows 28 capabilities that should be realized during this implementation. The implementation model has been evaluated using expert interviews and in a case study in a large Dutch software company.

Framework for Implementing Product Portfolio Management in Software Business

Whether a software product company takes up a project depends on the strategic decisions that are made with regard to an organization’s products. A software project needs to fit strategic goals and enable an organization to realize a vision through its software products. Making decisions on a strategic level, however, requires information of several related topics including technological trends and the product’s life cycle and surpasses the scope of an individual software project. Instead, these decisions are made on the level of the product portfolio. Product Portfolio Management (PPM) holds that an organization has to manage investment decisions over time following profit and risk criteria. Given the multitude of relevant topics and the interrelatedness between these topics, it has proven difficult to implement PPM processes in software businesses. To this end, we created the Portfolio Implementation Framework (PIF) consisting of (a) a competence model, giving an overview of the critical topics; (b) process-deliverable diagrams, which provide an implementation path for product portfolio management processes; and (c) a maturity matrix that comprises 32 capabilities, which should be realized during implementation. The maturity matrix also serves as an instrument for industry to assess, compare and improve portfolio management processes across organizations. The framework provides a holistic view on a step-by-step PPM process implementation and has proved its applicability in practice.