Thank you Betram for your comments. I will try to clarify inline.
> What observations are you making that lead you to this conclusion? Please be > specific. We kept record of the message groups used and the identity of the consumer (MDB instance) handling the last message in each group and logged whenever a message was assigned to a different consumer than the one that handled the last message for the group. We expected there to be no logging or at least each new consumer should be a newly created instance replacing an earlier consumer instance. However, we see many occurrences of this scenario logged with a fixed group of consumer instances. In other words: we see message groups being handled by different consumers constantly while the pool of consumer instances stays the same. > ENTMQ-261 [1] is not from the official Apache Jira project for ActiveMQ > Artemis [2]. It appears to be from a Red Hat issue tracker for their product > based on ActiveMQ Classic. It is not connected to the release of Apache > ActiveMQ Classic 6.1, and I can find no mention of ENTMQ-261 in the release > notes for ActiveMQ Classic 6.1. Yes, I know that. That is why I was asking if the same issue might be present in ActiveMQ Artemis assuming there might be overlap in the code bases. > ActiveMQ Artemis is based on the HornetQ code-base which was donated to > Apache ActiveMQ almost 10 years ago now. If you read the description on ENTMQ-261 you'll see that grouping was working as expected in HornetQ so I expect it would still be working ActiveMQ Artemis unless there's been some kind of regression that we're not aware of. OK, I think that answers my question then. > It's hard to say since the exact nature of the problem is still unclear. At the very least I would recommend upgrading WildFly so you're on a later release of ActiveMQ Artemis. Version 2.16.0 was released in late 2020 almost 4 years ago now. Lots of bugs have been fixed since then. Even if the problem you're seeing is a bug there won't be a bug-fix release for 2.16.0. You'd need to upgrade to the latest version to get it. That said, I'm still not sure this is actually a bug. We plan to upgrade Wildfly in the future so that may solve our issues. But since that may not happen anytime soon I was wondering if there might be some way to work around this. Thank you again for sharing your thoughts. Silvio
