Transacted sessions and order of messages

General Discussions
1

Hi all, I have a question. Suppose following publishing scenarios. All sessions are transacted, created from one particular connection, all steps are executed sequentially from one thread.

Scenario 1:
Session1.transaction1 → 1,2
Session1.commit
Session2.transaction2 → 3,4
Session2.commit
Session1.transaction3 → 5,6
Session1.commit

Scenario 2:
Session1.transaction1 → 1,2
Session1.commit
Session1.transaction2 → 3,4
Session1.commit
Session1.transaction3 → 5,6
Session1.commit

What are the messages order guarantees in Solace ?
According JMS spec (6.2.9.2) " A transaction’s order of messages to a particular destination is significant"
It seems like in scenario 2 messages will be ordered and consumer will consume 1,2,3,4,5,6.
Am I right ?
What about scenario 1 ?
Thanks.

2

Hi Игорь Попов…! Yes, you’re correct: the order of messages in both scenarios would be maintained, and the consumer would receive 1, 2, 3, 4, 5, 6. Even if you weren’t to use transactions, order would be maintained since you’re publishing from a single thread.

3

Expanding on what Aaron said, in general, the ordering rule in Solace is “the order on reception is preserved.” In other words, what matters is the order the messages were received at the broker. For single threaded producers that’s easy… :smile: