Hi I've been looking at a problem I ran into here where messages are consumed, and acknowledged, but are then later redelivered to the consumer again after a broker restart.
The consumer is running with transacted sessions, and looking in KahaDB, I can see a KAHA_REMOVE_MESSAGE_COMMAND, with the local transaction ID added to the journal, and then a KAHA_COMMIT_COMMAND after it. Some time later, I see the exact same KAHA_REMOVE_MESSAGE_COMMAND appended to the journal again, with the exact same transaction information, but no corresponding KAHA_COMMIT_COMMAND. This appears to follow a KAHA_REWRITTEN_DATA_FILE_COMMAND. It looks like the ack compaction method is forwarding the acknowledgement, but not the commit - it appears that the commit is only forwarded in the case of an XA transaction. I notice that there are some tests around this in AMQ-7067. I've managed to reproduce this with a further test case in AMQ8067Test.java, and I have created a PR for this here: https://github.com/apache/activemq/pull/636, and backported to 5.16.x https://github.com/apache/activemq/pull/637 and 5.15.x. https://github.com/apache/activemq/pull/638 Are there other cases that should be tested around this? Thanks Jon
