To improve binary hardening, we should enable full relro in the OpenJDK builds. Currently
our build settings enable only partial relro (they miss z,now).
See https://www.redhat.com/en/blog/hardening-elf-binaries-using-relocation-read-only-relro

"Both partial and full RELRO reorder the ELF internal data sections to protect them from being overwritten in the event of a buffer-overflow,
but only full RELRO mitigates the above mentioned popular technique of overwriting the GOT entry to get control of program execution."

See also :
https://wiki.debian.org/Hardening

Some documentations/blogs mention slight performance impact of full relro (for startup performance).
However my quick checks on an example Linux server show not much impact.