Just wrote a blog post about the new session level batch size feature. http://blog.arnoldgalovics.com/2016/06/09/session-level-hibernate-jdbc-batching
Oliver Gierke pointed out, when using the concept of MethodInterceptors the batch size should be set exactly to the original size as was before after a successful or exceptional execution.
The current org.hibernate.SharedSessionContract#setJdbcBatchSize method signature makes it impossible to do, because of the primitive integer parameter.
As I discussed with Vlad Mihalcea, this can be fixed. https://twitter.com/ArnoldGalovics/status/740897265854877696