Software Engineering Processes for Self-Adaptive Systems

Abstract

In this paper, we discuss how for self-adaptive systems some activities that traditionally occur at development-time are moved to runtime. Responsibilities for these activities shift from software engineers to the system itself, causing the traditional boundary between developmenttime and run-time to blur. As a consequence, we argue how the traditional software engineering process needs to be reconceptualized to distinguish both development-time and run-time activities, and to support designers in taking decisions on how to properly engineer such systems.Furthermore, we identify a number of challenges related to this required reconceptualization, and we propose initial ideas based on process modeling. We use the Software and Systems Process Engineering Meta-Model (SPEM) to specify which activities are meant to be performed off-line and on-line, and also the dependencies between them. The proposed models should capture information about the costs and benefits of shifting activities to run-time, since such models should support software engineers in their decisions when they are engineering self-adaptive systems.

Mechanisms for Leveraging Models at Runtime in Self-adaptive Software

“…Methods, techniques, and tools should be tied together to provide an end-to-end development approach that supports evolution before and after the M@RT-based system becomes operational. This problem has also been identified in [1] for self-adaptive software systems in general.…”

“…Models at runtime (M@RT) research focuses on how models describing different aspects of a software system and its environment (e.g., requirements, design, runtime configuration) can be used to manage the complexity of effectively adapting software systems at runtime [11,40]. This chapter is a distillation of discus-sions held in a working group at the Dagstuhl Seminar on Models@run.time 1 . The working group discussions focused on challenges associated with developing M@RT mechanisms to support runtime software adaptation.…”

Modeling Collaborations in Adaptive Systems of Systems

“…Development Requirements R-18* Offline and Online: Due to software evolution and aging [16,77], there is a coexistence of software adaptation activities that are performed offline or online. Performing online adaptation is realized by the adaptation engine, which enables an appropriate derivation of the behavior according to changing needs.…”

“…In such cases, the software must be externally adapted, e. g., by software maintenance activities, which is called offline adaptation. Andersson et al [16] show that the coexistence of offline and online adaptation is required. As a consequence, a modeling language should support both kinds of online and offline adaptations as well as their coexistence.…”

“…They end up with challenges of the explicit modeling of collaboration aspects (R-03, R-07) as well as the specification of partial knowledge (R-11). With focus on offline and online adaptation steps within the software engineering process, Andersson et al [16] comprehensively discuss the problem but do not present a working solution that integrates both processes.…”