Java fails to start when classes.tar is not loaded via the vfs tar plugin

Hello Genodians

I'm tying to optimize the startup time of a java application (ARM board), as starting the JVM takes several seconds on our board.

To do this, I tried to move the classes.tar in to a separate vfs component [1]. This crashes the JVM with the following error message:

[init -> java] Error occurred during initialization of VM [init -> java] java.lang.NoClassDefFoundError: java/util/concurrent/ConcurrentHashMap [init -> java] at java.lang.WeakPairMap.<init>(java.base/WeakPairMap.java:47) [init -> java] at java.lang.Module.<clinit>(java.base/Module.java:267)

Can anyone tell me, why this happens? Is there a way to fix this?

[1] https://github.com/trimpim/genode-world/commit/3ec7d915e20576a786a3e89decb49...

Best regards, Primin