Hello,
yes I can share the dumps without trouble. How can I send them to you?
Besides, I would like to share with you the following changeset[1], for your consideration. It helped us to reduce the heap when using Hibernate 3.6. But it seems to be not enough after the upgrade to Hibernate 5.3.
[1] https://github.com/alostale/hibernate-orm/commit/612675c92c97bacd61d0c07a0802344eca42f5c0