A Design-Oriented Classification of Microservice Smells

Context: Introduction of bad smells can generate negative consequences on the quality of microservices. It is essential to gather state-of-the-art knowledge on these smells and understand the challenges they present. This will benefit researchers and practitioners in mitigating the consequences of smells in microservice-based systems. Objective: The main goal of this study is to present a comprehensive catalogue of microservice smells. Method: To document the advancements and best practices in the field of microservice smells., we performed a multivocal literature review study incorporating both academic and grey literature sources. We systematically analyzed 34 studies published from the beginning of 2014 until the end of 2023 by following standard guidelines. Results: 38 bad smells in microservices are identified and cataloged in 10 different types. Conclusion: Research gaps and open challenges are highlighted in this study. This will give directions to other researchers and practitioners towards addressing challenges posed by smells in microservices.