问题
In Microsoft Azure, under service bus, you can see activity graphs for the different queues/topics etc.
The graph shows various different lines, such as incoming messages, outgoing messages, successful requests etc.
What is a Request? And what is a Message?
Requests seem to be constantly occurring and often significantly large than the number of messages (in topics). Even though the number of servers listening to the queue remains the same - sometimes the number of requests will dramatically increase without seeing any change in the number of messages.
回答1:
I assume that a request is a poll on a queue / subscription, even if that didn't result in a message being pulled. With the OnMessage message pump model , you typically wait 'forever' until a message arrives, resulting mostly in an equal number of receives & messages. But when your role/thread/pump stops and restarts, that will trigger a new receive, even if no message was found.
来源：https://stackoverflow.com/questions/22861571/azure-service-bus-whats-a-request-and-a-message