Résumé
Our main findings are: i) when no app component is replicated, MSA outperforms the monolithic architecture; ii) the monolithic architecture shows performance and availability improvement when replicating the entire app; iii) the replicated MSA version reaches a ceiling when not replicating its routing part (i.e., the API gateway), showing worse response times compared to the replicated monolith; iv) when replicating the API gateway, the MSA version reaches optimal performance with fewer replicates than the monolith; v) when not replicating services, MSA consumes more CPU resources than the monolithic architecture; vi) when scaling up, the MSA version is more efficient than the replicated monolith in terms of memory usage, and it can better exploit CPU resources; vii) when not replicating services, MSA consumes more energy than the monolithic architecture, whereas when scaling up, the MSA version is more efficient than the replicated monolith; MSA version reaches a good balance between CPU and memory usage.