On the temporal behaviour of a large-scale microservice architecture

Microservices are fast becoming the predominant architectural style for orchestrating online services due to the advantages they can bestow over monolithic systems. However, as microservice architectures grow in size they quickly become complicated to understand and manage. Their characteristics raise the question as to whether they may behave like complex systems. In this paper, we use tools from graph theory to analyse the static and temporal dependency structure of a large-scale microservice architecture. We find that the dependency structure can fluctuate significantly at run time and further, that it can be clustered into distinct and persistent states with recognisable characteristics. Importantly, we show that these states can have functional implications for the performance of the microservice architecture. These early findings suggest that microservices may indeed behave like complex systems and, as such, would benefit from complex systems thinking when approaching their management and development.