[hibernate-issues] [Hibernate-JIRA] Closed: (EJB-351) Optimistic Locking Deadlocks with Application Manged EM in Threaded Environment

Optimistic Locking Deadlocks with Application Manged EM in Threaded Environment ------------------------------------------------------------------------------- Key: EJB-351 URL: http://opensource.atlassian.com/projects/hibernate/browse/EJB-351 Project: Hibernate Entity Manager Issue Type: Bug Components: EntityManager Affects Versions: 3.3.2.GA Environment: Annotations 3.3.1.GA Core 3.2 Windows XP Pro Netbeans 6.01 Sun JDK 1.6.04 MSSQL 2000 Reporter: Allen Harvey Attachments: hibernateJPAtest.zip I have posted about this issue in the forums here: http://forum.hibernate.org/viewtopic.php?t=985460, but have received no reply. I am hoping it is a bug, and not a mistake on my part. When using an application managed entity manager in a concurrent environment, the database is deadlocking. The scenario is this: Create several bank accounts Persist them Create many (10) clients Clients simultaneously transfer money randomly among the accounts as fast as possible Each transfer between two accounts is a transaction Optimistic lock exceptions are expected and handled (a new em is created and the transaction retried). Depsite having annotated the account entity (@Version), settings ordered updates, using a thread-local entity manager, and setting the MS SQL 2000 db to read committed, the database deadlocks. I have created a small sample application that reproduces the problem, it is attached. Finally, I tried this on Mysql 5.x as well, and that database also deadlocked, so it doesn't appear to be a database driver issue.