[jboss-user] [jBPM] - Concurrency issue with LocalTaskService

Jon Kranes [https://community.jboss.org/people/jkranes] created the discussion "Concurrency issue with LocalTaskService" To view the discussion, visit: https://community.jboss.org/message/817047#817047 -------------------------------------------------------------- I am running into a concurrency issue in my JBPM 5.4 application.  At first I thought it was related to thread safety of the StatefulKnowledgeSession issue discussed elsewhere, but I am able to recreate the issue without any session at all. I am using the Spring JtaTransactionManager with annotated transaction boundaries, with MySQL, and running on AS 7.1.1. The Spring configuration looks like this: <jee:jndi-lookup id="emf" jndi-name="persistence/myEmf"/><bean id="sel" class="org.drools.SystemEventListenerFactory"factory-method="getSystemEventListener" /><bean id="jbpmTaskService" class="org.jbpm.task.service.TaskService"c:emf-ref="emf" c:systemEventListener-ref="sel" /><bean id="localTaskService" class="org.jbpm.task.service.local.LocalTaskService" c:taskService-ref="jbpmTaskService" /><bean id="jpaDialect" class="org.springframework.orm.jpa.vendor.HibernateJpaDialect" /><bean id="txManager" class="org.springframework.transaction.jta.JtaTransactionManager" /><tx:annotation-driven transaction-manager="txManager" /> And the code triggering the problem is this: List<TaskSummary> tasks = localTaskService.getTasksAssignedAsPotentialOwner(assignee, "en-UK"));        for (TaskSummary summary: tasks){              // ...                 org.jbpm.task.Task t = localTaskService.getTask(summary.getId());              // ....             }         } Note that this code is annotated as @Transactional If I call this code from a single thread or inside a synchronized block I have no problems.  If I call it from multiple concurrent threads, I consistently trigger the error: java.lang.IllegalStateException: Trying to return an unknown connection2! org.jboss.jca.adapters.jdbc.jdk6.WrappedConnectionJDK6@2a77a3c4 The trigger seems to be the inner call to the localTaskService.  With just the outer call I have no problems.  Googling this error, it seems this was a common problem with older hibernate versions (2.x) but I did not find any references to people seeing it for hibernate 4.x. Any ideas? Thanks, Jon -------------------------------------------------------------- Reply to this message by going to Community [https://community.jboss.org/message/817047#817047] Start a new discussion in jBPM at Community [https://community.jboss.org/choose-container!input.jspa?contentType=1&...]