A decision model for selecting FaaS platforms

Abstract

Context: Serverless computing is an umbrella paradigm that encompasses multiple service categories, including Function-as-a-Service (FaaS) and Backend-as-a-Service (BaaS). It has reshaped cloud application development by abstracting infrastructure management tasks such as provisioning, scaling, and operational maintenance from developers, thereby enabling greater focus on application logic. To realize these benefits, organizations need to select among various FaaS platforms such as AWS Lambda, Google Cloud Functions, Azure Functions, and Apache OpenWhisk to develop their serverless applications. Nevertheless, the increasing number of available FaaS platforms and their heterogeneous characteristics (e.g., timeout constraints, cold-start behavior, memory and package size limits, and event-source integration) make platform selection complex and knowledge-intensive for the decision makers. Objective: The main objective of this study is to support decision-makers in selecting appropriate FaaS platforms by designing an effective and systematic decision model. The model aims to simplify the selection process, reduce time and effort, and provide deeper insights into platform suitability based on specific organizational requirements. Method: We employed a mixed-method research design to develop a decision model for the FaaS platforms selection problem. The model contains a mapping of 219 features across 16 FaaS platforms. Results: The model was evaluated through five real-world case studies conducted at different software development companies. It suggests and prioritizes more than one FaaS platform based on the participants’ requirements. The case study participants reported that the model offered valuable insights and significantly simplified the selection process by reducing the time and costs associated with the decision-making process. Conclusion: We observe in the empirical evidence that decision-makers can make more rational, efficient, and effective decisions with the decision model. Additionally, the model provides reusable insights that can support future research, such as developing new frameworks and solutions for emerging challenges in serverless computing.