I was trying the nice new Spring Boot startup tracking feature and used BufferedApplicationStartup to collect initialization data. I found that the collected data is drained from the buffer after each request. In particular, it took me a moment to recognize that the most important data is lost after the first request. As discussed with @bclozel this could be emphasized in the documentation, cf. https://stackoverflow.com/questions/65413579/spring-boot-bufferedapplicationstartup-drained-after-first-request