RabbitMQ and message priority

Question

Does RabbitMQ have any concept of message priority? I have an issue were some more important messages are being slowed down due to less important messages sitting before it

Answer 1

IIRC RabbitMQ still uses the AMQP protocol version 0.9.1 (get the spec here). The spec definitely mentions message priority:

Messages may have a priority level. A high priority message is sent ahead of lower     priority messages
waiting in the same message queue. When messages must be discarded in order to maintain a specific
service quality level the server will first discard low-priority messages.

And:

Note that in the presence of multiple readers from a queue, or client transactions, or use of priority fields,
or use of message selectors, or implementation-specific delivery optimisations the queue MAY NOT
exhibit true FIFO characteristics.

The spec says priority is a MUST, so I guess RabbitMQ should implement it, but you may want to consult its documentation.