did you have maxSession at 1 when it happened?
When you have multiple sessions on the MDB you will have multiple instances consuming on multi-threads and you could have the impression of out of order because of that.
or do you have scheduled redelivery configured? if you cancel a message it may be scheduled to be redelivered after some time what would give you the out of order as well.
thank you for your reply.
Yes, I have had maxSession set to 1.
I do not have sheduled redelivery at all.
Moreover, in JBoss logs I can see all messages are managed by one thread.
As far as I know lots of users consume messages sequentially using the kind of approach you are using. I would expect it to work. Can you provide a reproducible test-case based on one of the Java EE examples we ship with HornetQ already?