I would like to know when exactly does the Mule VM transport perform the message persistence task, is it similar to the JMS brokers where they perform the persistence before sending out an ack or is it done in some other fashion ?
Does the VM internally have a broker of sorts which actually takes care of the persistence ?
A related question would be if I had 2 mule instances participating in a Mule cluster both using VM transports and have some messages in flight and if both instances went down at the same instance, would I be able to recover my messages ?
1) By default, when persistence is enabled, the VM connector stores messages in a file store.
2) In order to ensure messages are not lost whilst being processed, it is possible to start a transaction on the VM inbound endpoint, this will consume the message only when the flow successfully processes the messages, else it is not consumed.