Null output parameters

[wolski0420]

I'm load testing multiple rabbit servers. I'm using -o flag to dump results to the local file. I've noticed that I have one data column filled by NULL and it is "returned (msg/s)" column.

I have some questions:

1. What does it exactly mean "returned (msg/s)". Is it "number of messages returned to the rabbit server from clients (sender/receiver) per second"?
2. How can I enable it? Should I use some additional flags? Or it just depends on test situation?
3. Is it connected with NACKing messages? If yes - how? (my reasoning is, if client nack received message, it is going back to the server what implies "returned message"). I'm asking because I've noticed that "nack (msg/s)" column is not NULLed but has 0 in all rows.

I'm not advanced in RabbitMQ protocol. At this moment I'm trying to understand the behavior of Rabbit basing on load tests provided by PerfTest.

[michaelklishin]

Your questions are covered in Unroutable Message Handling.