A Metrics Framework for Evaluating Microservices Architecture Designs

  • Omar Al-Debagy Department of Electronics Technology, Budapest University of Technology and Economics, Hungary https://orcid.org/0000-0002-1988-5078
  • P. Martinek Department of Electronics Technology, Budapest University of Technology and Economics, Hungary
Keywords: microservices, software metrics, lack of cohesion, service granularity, service complexity


Microservices are becoming a more popular software architecture among companies and developers. Therefore, there is a need to develop methods for quantifying the process of measuring the quality of microservices design. This paper has created a novel set of metrics for microservices architecture applications. The proposed metrics are the Service Granularity Metric “SGM”, the Lack of Cohesion Metric “LCOM”, and the Number of Operations “NOO”. The proposed metrics measure the granularity, cohesion, and complexity of individual microservices through analyzing the application programming interface “API”. Using these metrics, it is possible to evaluate the overall quality of the design of microservices applications. The proposed metrics were measured on 5 applications with different sizes and business cases. This research found that the value for the SGM metric needs to be between 0.2 and 0.6. Besides, the value of LCOM metric for a microservice needs to be between 0 and 0.8 with less than ten operations per microservice. These findings can be applied in the decomposition process of monolithic applications as well.


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Author Biographies

Omar Al-Debagy, Department of Electronics Technology, Budapest University of Technology and Economics, Hungary

O. Al-Debagy started pursuing his PhD degree in 2017 at Budapest University of Technology and Economics. He obtained his BSc in Information Technology from University of Kurdistan – Hewler in 2012. Then he got his MSc in Information Systems Engineering from Cyprus International University in 2015. He has an extended experience in web development and technologies. Also, he was an assistant lecturer at the Lebanese French University from 2015 until 2016. Furthermore, he worked as a web developer for USAID/Iraq Governance Strengthening Project from 2016 to 2017. Nowadays he is finishing his PhD research in microservices decomposition methods and techniques.

P. Martinek, Department of Electronics Technology, Budapest University of Technology and Economics, Hungary

P. Martinek received his B.Sc, M.Sc. and PhD degrees in Computer Engineering from Budapest University of Technology and Economics, Hungary. Dr. Martinek is an associate professor at the Department of Electronics Technology at BME since 2012. He is the recipient of the 2010 IBM Faculty award. His main research area is Enterprise Application Integration (EAI), but he also studies production scheduling and optimization of manufacturing processes by machine learning methods.


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