7.2.4. Query Sender Capacity
When using asynchronous message sending, three sender properties are available to ascertain the state of the asynchronous calls. They are:
- Sender Capacity
- The maximum number of asynchronously sent messages that can be pending acknowledgement at any given time. By default this is
UNLIMITED, but it can be changed to constrain the number of unsettled asynchronous calls. An attempt to make a further asynchronous call when the sender is at capacity will block until another sent message is acknowledged by the broker.- C++
sender.getCapacity()
- Python
sender.capacity
- Sender Unsettled
- The number of asynchronous sends pending acknowledgement from the broker.
- C++
sender.getUnsettled()
- Python
sender.unsettled()
- Sender Available
- The number of additional asynchronous calls that the sender can accept at the moment. This value is available as a property, but can also be computed from
sender.capacity-sender.unsettled.- C++
sender.getAvailable()
- Python
sender.available()
