I'm using JbossCache 1.1 as a transactional cache for Hibernate 2.1.6. Currently we're running on Tomcat 4.1.30 with JOTM 1.5.3 as the TransactionManager. Database is Oracle 10g.
Frequently, Hibernate is running into deadlock-situations with TImeoutException as a result while putting data into any of the two nodes (or their children):
An isolation level is per TreeCache, you cannot define separate isolation levels for separate regions inside the same TreeCache.
This is a deficiency (IMO) of JTA. You *could* set the isolation level in JDBC per transaction*, but you cannot do this using J2EE transactions.