Architectural Tactics for Energy Efficiency: Review of the Literature and Research Roadmap

The energy consequences of software are rapidly growing: at the high-end, server farms consume enormous amounts of energy; at the low-end there is ever-increasing emphasis on battery-powered mobile and Internet-of-Things (IoT) devices with equally increasing complex usage scenarios. Conversely, there has been little attention to how software architectures can be designed for energy efficiency. While other software qualities—--think of performance or availability--—have been extensively studied, there is little research on how to reason about energy-consumption as a first-class citizen. We provide a basis for reasoning about design decisions for energy efficiency by deriving a kit of reusable architectural tactics derived from literature. We use the well-known open-search and snowballing methodologies to attain primary studies, and subsequently used thematic coding of such studies to identify recurrences and commonalities among the design strategies presented. The result of this process is a set of 10 architectural tactics for energy efficiency. These tactics provide a rational basis for architectural design and analysis for energy efficiency

A systematic literature review on Energy Efficiency in Cloud Software Architectures

Cloud-based software architectures introduce more complexity and require new competences for migration, maintenance, and evolution. Although cloud computing is often considered as an energy-efficient technology, the implications of cloud-based software on energy efficiency lack scientific evidence. At the same time, energy efficiency is becoming a crucial requirement for cloud service provisioning, as energy costs significantly contribute to the Total Cost of Ownership (TCO) of a data center. In this paper, we present the results of a systematic literature review that investigates cloud software architectures addressing energy efficiency as a primary concern. The aim is to provide an analysis of the state-of-the-art in the field of energy-efficient software architectures

Sheds for Antarctica: the environment for architectural design and practice

This work frames the architectural practice of Antarctica; a young practice environment characterised by loose collaboration and participation in diverse design activities. The architectural projects forming this research have surfaced three central propositions; about a mode of design practice, a type of architectural space, and an ethical position towards architecture. Each of these share the impulse to be immersed environmental influences affecting architecture. This document reflects on these ideas through the lens of a series of themes: noise, junk, longevity, and participation. Each of these themes describes the environment and context in which architectural design takes place. Through these designs, the architectural model of the shed is examined; a form which is characterised by loose and robust space. Together these reflections form a position towards sustainability that is applicable to architecture. That position foregrounds participation in the breadth of the imperfect environment for building; accommodation of change in that environment, and an open robust design process. In doing this it seeks to contribute to debates which span between architectural composition and the social forces on architecture, re-engaging the two with each other. The design projects, and the position elaborated through them, set out a territory for Antarctica’s ongoing design research and collaborative methods

Energy-Efficient Software

The energy consumption of ICT is growing at an unprecedented pace. The main drivers for this growth are the widespread diffusion of mobile devices and the proliferation of datacenters, the most power-hungry IT facilities. In addition, it is predicted that the demand for ICT technologies and services will increase in the coming years. Finding solutions to decrease ICT energy footprint is and will be a top priority for researchers and professionals in the field. As a matter of fact, hardware technology has substantially improved throughout the years: modern ICT devices are definitely more energy efficient than their predecessors, in terms of performance per watt. However, as recent studies show, these improvements are not effectively reducing the growth rate of ICT energy consumption. This suggests that these devices are not used in an energy-efficient way. Hence, we have to look at software. Modern software applications are not designed and implemented with energy efficiency in mind. As hardware became more and more powerful (and cheaper), software developers were not concerned anymore with optimizing resource usage. Rather, they focused on providing additional features, adding layers of abstraction and complexity to their products. This ultimately resulted in bloated, slow software applications that waste hardware resources -- and consequently, energy. In this dissertation, the relationship between software behavior and hardware energy consumption is explored in detail. For this purpose, the abstraction levels of software are traversed upwards, from source code to architectural components. Empirical research methods and evidence-based software engineering approaches serve as a basis. First of all, this dissertation shows the relevance of software over energy consumption. Secondly, it gives examples of best practices and tactics that can be adopted to improve software energy efficiency, or design energy-efficient software from scratch. Finally, this knowledge is synthesized in a conceptual framework that gives the reader an overview of possible strategies for software energy efficiency, along with examples and suggestions for future research

A tale of three systems : case studies on the application of architectural tactics for cyber-foraging

Cyber-foraging is a technique to enable mobile devices to extend their computing power and storage by offloading computation or data to more powerful servers located in the cloud or in single-hop proximity. In previous work, we developed a set of reusable architectural tactics for cyber-foraging systems. We define architectural tactics as design decisions that influence the achievement of a system quality. In this article we present the results of three case studies to validate the application of the tactics to promote their intended functional and non-functional requirements. The first two case studies focus on the identification of architectural tactics in existing cyber-foraging systems. The third case study focuses on the development of a new cyber-foraging system using the architectural tactics. The results of the case studies are an initial demonstration of the validity of the tactics, and the potential for taking a tactics-driven approach to fulfill functional and non-functional requirements for cyber-foraging systems. (C) 2019 Elsevier B.V. All rights reserved