Overview
During an application startup process, Spring Boot performs a lot of work in the background. This work involves creating Spring Application Context, creating various beans, auto-wiring, and auto-configuration of various components, and finally, starting the application. When a Spring Boot Application has a slow startup, it can be one or more beans and related dependencies taking longer to initialise and slowing down the entire process.
Profiling Spring Boot application doesn’t often help in diagnosing the startup issues. This is because there are a number of beans getting initialised and it is really difficult to figure out which ones are causing the latency. Spring Boot Application Startup Metrics are useful for such cases.