Difference between Pending Messages and Enqueue Counter in Active MQ?

Question

In the Active MQ Admin console of what is the difference between "Number Of Pending Messages" and "Messages Enqueued"? When a Message is placed on to the queue, should both these values should match?

Solution 1

pending messages = number of messages CURRENTLY waiting for delivery in the destination (the current size of the queue)

enqueued messages = number of messages that where enqueued in the destination since the last statistic reset. This number can only rise.

dequeued messages = messages delivered from the destination to consumers. this number can be higher that the number of enqueued messages if a message was delivered to multiple consumers (topics).

Solution 2

Messages Enqueued = Number of messages sent to the queue since the server start

Messages Dequeued = Number of messages received+deleted since the server start