Microservice Transition and its Granularity Problem: A Systematic Mapping Study

Microservices have gained wide recognition and acceptance in software industries as an emerging architectural style for autonomic, scalable, and more reliable computing. The transition to microservices has been highly motivated by the need for better alignment of technical design decisions with improving value potentials of architectures. Despite microservices' popularity, research still lacks disciplined understanding of transition and consensus on the principles and activities underlying "micro-ing" architectures. In this paper, we report on a systematic mapping study that consolidates various views, approaches and activities that commonly assist in the transition to microservices. The study aims to provide a better understanding of the transition; it also contributes a working definition of the transition and technical activities underlying it. We term the transition and technical activities leading to microservice architectures as microservitization. We then shed light on a fundamental problem of microservitization: microservice granularity and reasoning about its adaptation as first-class entities. This study reviews state-of-the-art and -practice related to reasoning about microservice granularity; it reviews modelling approaches, aspects considered, guidelines and processes used to reason about microservice granularity. This study identifies opportunities for future research and development related to reasoning about microservice granularity.Comment: 36 pages including references, 6 figures, and 3 table

A Reference Architecture and Roadmap for [email protected] Systems

International audienceThe key property of [email protected] systems is their use and provision of manageable reflection, which is characterized to be tractable and predictable and by this overcomes the limitation of reflective systems working on code, which face the problem of undecidability due to Turing-completeness. To achieve tractability, they abstract from certain aspects of their code, maintaining runtime models of themselves, which form the basis for reflection. In these systems, models form abstractions that neglect unnecessary details from the code, details which are not pertinent to the current purpose of reflection. Thus, [email protected] systems are a new class of reflective systems, which are characterized by their tractability, due to abstraction, and their ability to predict certain aspects of their own behavior for the future. This chapter outlines a reference architecture for [email protected] systems with the appropriate abstraction and reflection components and gives a roadmap comprised of short-and long-term research challenges for the area. Additionally, an overview of enabling and enabled technologies is provided. The chapter is concluded with a discussion of several application fields and use cases