Possible problem in concurrent signalling from multiple threads --------------------------------------------------------------- Key: JBPM-1071 URL: http://jira.jboss.com/jira/browse/JBPM-1071 Project: JBoss jBPM Issue Type: Bug Components: Core Engine Affects Versions: jBPM jPDL 3.2.2 Environment: Linux 2.6.21-1.3228.fc7 #1 SMP Tue Jun 12 14:56:37 EDT 2007 x86_64 x86_64 x86_64 GNU/Linux MySQL 5.0.22 Reporter: Jiri Pechanec Assigned To: Len DiMaggio Priority: Critical Attachments: expl.tar.gz, LockingTest.java, log.txt Attached is a simple test case that 1) Deploys process definition with two nodes 2) Starts the process instance that will go to the wait state on first node 3) Starts 20 threads that tries concurrently signal the same process instance 4) The second node writes a record to the database The test case needs to be executed multiple times to see the incorrect behaviour. This is an example of run output Isol 8 Action 1 Action 2 Action 2 Action 2 Action 2 Action 2 1 Action 2 1 Action 2 1 Action 2 1 Signalist 5 Signalist 6 Signalist 8 Signalist 12 Signalist 7 Signalist 13 Signalist 14 Signalist 15 Signalist 9 Signalist 16 Signalist 17 Signalist 18 Signalist 4 Success 7 Failure 13 Explanation of the outcome 4 threads successfully executed the node action including database operation. All database opeartion were comitted (4 new records were created) 3 threads successfully executed the signal operation but no real action was performed 13 threads attempted to execute the signal operation but ended with an exception