Repository queries taking collection parameters are limited to 32K collection items. (This is caused by Hibernate PostgreSQL driver having limit of 32767 bind variables per statement.)
For example, org.onap.cps.spi.repository.FragmentRepository#deleteByAnchorIn:

@Modifying
@Query("DELETE FROM FragmentEntity WHERE anchor IN (:anchors)")
void deleteByAnchorIn(@Param("anchors") Collection<AnchorEntity> anchorEntities);

This would throw an exception if supplied with a collection of 32,768 items.

This task to remove those limits (and write tests to verify).