Foundations of Scalable Software Architectures

Scalability is a driving software quality attribute for many contemporary, Internet-facing systems. Applications that fail or perform slowly and reject requests under high request loads are rapidly deserted by users, and the resulting business and societal impacts can be profound. This paper summarizes some of the key foundational issues of scalable software and system architectures. Design patterns and tactics needed to ensure scalability are briefly described for both the processing and persistence layers. A case study of a novel approach to balance performance and cost is also presented and we show how this approach can be applied to cloud-based scalable architectures. Detailed coverage of these issues was presented in a tutorial at ICSA 2022.