I'll just mention I did some experiments around this in a branch of mine:
https://github.com/aclement/graal/tree/agent-filtering

It's a bit unfinished but the principles are there:

• it discovers META-INF/native-image entries on the classpath (in directories, don't think it goes into jars yet)
• loads them up into a separate configurationset
• subtracts that configurationset from the collected set before it is written out (possible to do this as you go I suppose, I just did something quick).
• it attempts to simplify entries in the agent output as much as possible, so it is quite granular, it doesn't just remove them if they are identical, it strips them down (for example if the existing config named 3 methods and the computed config contained 5, it should remove 3 from the computed config)

For our webmvc-tomcat sample, I saw the line count for reflect-config.json go from 2800 to 1900.

Hey @aclement! Your approach for this change is good, and the principles it follows (filtering configuration when it's written out and simplifying entries) is basically the same as it's now implemented on master: a461aa0

There are two different agent flags related to this mode:

• experimental-omit-config-from-classpath omits configuration present on the classpath, both in directories and JARs
• config-to-omit=<path> omits configuration from a specified directory

This feature won't be in the upcoming 21.2 release, but it's on master and should soon be available in the dev builds. If anyone has a chance to test it out - please do and let me if it works for you

I'll close this issue as the feature had made it into 21.3 - let me know if you hit any issues/have any questions about the feature

FYI spring-attic/spring-native#617 (comment)

Is there any work planned to improve the filtering as per @sdeleuze comment?