Optimize startup time SpringCacheAnnotationParser

[philwebb]

Looking at the PetClinc it appears that SpringCacheAnnotationParser might be a hotspot. It searches every method in the app for @Cache... annotations. Not sure if there's much we can do, it might be a Spring issue. It seems a little related to the performance of AnnotatedElementUtils.

[philwebb]

[philwebb]

@jhoeller Can you see anything obvious that could be done to improve the annotation processing performance. I wonder if calling isAnnotated first and perhaps somehow caching to save on meta-annotation recursion?

[snicoll]

@philwebb I am confused, SpringCacheAnnotationParser is in Spring Framework isn't it?

[philwebb]

@snicoll Yes, I have a feeling that this will ultimately be something we can't fix in Boot.

[philwebb]

This is a known issue (also with EventListener) and we're investigating various options in Spring Framework see spring-projects/spring-framework#22175