This proposes a review of symbol stripping. Symbols aid diagnostics but take up space.

I had a brief look at adoptopenjdk/openjdk11:x86_64-alpine-jdk-11.0.6_10 and adoptopenjdk/openjdk11:x86_64-alpine-jdk-11.0.6_10-slim.

https://github.com/AdoptOpenJDK/openjdk-docker/blob/master/slim-java.sh#L247
libjvm.so stripped is around 18MB, full is 22MB. A 20% difference. But when compared with other file sizes - largest /opt/java/openjdk/lib/modules at 135MB, the increase is not so significant.

As the files a stripped in both full and slim and I haven't built from source I don't know how much space the symbols are taking.
In the context here the troubleshooting value may be more than the space saving on these 2 files.
Resolving #317 may provide some space for symbols to be retained.

I don't have the full numbers, the image sizes etc, but it appears that it may be possible to retain symbols without significantly bloating the slim image size.