Eager Quarkus components initialization for good response times of first request after startup

[SpaceFox]

Hi everyone!

As far as I understand, Quarkus and all its modules (OIDC handling, Panache…) are designed for lazy initialisation. This has a lot of advantages but leads to slow "first access" (very first request can take more than a second; first access to any endpoint is way slower than consecutive ones).

I have a case in where all my requests must responds quick, event after a container restart.

I have seen I can use eager instantiation of beans. This works for my beans, but actually most of time spent in initialisation are from Quarkus dependencies (in order: vert.x/http stuff, OIDC, Panache/Hibernate). I tried to add these dependencies in a @Startup method, but this look dirty and is inefficient as I don’t know which beans to create to have a correct initialisation of these dependencies.

The best I have found for now is to add a HTTP call to some actual endpoints on first health-check call. In this case, the first HC call initialise everything and only when it’s done, the container is flagged as "ready".

Do you see a better way to achieve the goal "the first call on a 'ready' Quarkus container must be as reactive as all other ones"?

Thank you in advance!