Container-managed EXTENDED persistence context is always joined with transaction even if UNSYNCHRONIZED ------------------------------------------------------------------------------------------------------- Key: WFLY-3105 URL: https://issues.jboss.org/browse/WFLY-3105 Project: WildFly Issue Type: Bug Security Level: Public(Everyone can see) Components: JPA / Hibernate Affects Versions: 8.0.0.Final Reporter: Christian Bauer Assignee: Scott Marlow Fix For: 8.0.1.Final https://github.com/weld/wildfly/blob/master/testsuite/integration/basic/s... Change this test to {code}@PersistenceContext(type = EXTENDED, synchronization = UNSYNCHRONIZED){code} and it will break. Looks like an extended PC is always joined to the transaction and flushed on commit, the unsynchronized mode is ignored. From what I can see this is not specified and indeed would make the whole new UNSYNCHRONIZED feature kind of pointless. It's primary use case is propagation of unflushed/unsynchronized extended PC from a SFSB to other beans while keeping transactions intact.