We are pleased to announce the immediate availability of RabbitMQ 3.6.0, a new version of the broker that comes packed with lot of new features. Before we go on, you can obtain it here: https://www.rabbitmq.com/download.html.

This release brings many improvements in broker features, development environment for our contributors, and security. Let’s take a look at some of the most significant ones.

In order to prevent fast publishers from overflowing the broker with more messages than it can handle at any particular moment, RabbitMQ implements an internal mechanism called credit flow that will be used by the various systems inside RabbitMQ to throttle down publishers, while allowing the message consumers to catch up. In this blog post we are going to see how credit flow works, and what we can do to tune its configuration for an optimal behaviour.

For a while people have looked for ways of implementing delayed messaging with RabbitMQ. So far the accepted solution was to use a mix of message TTL and Dead Letter Exchanges as proposed by James Carr here. Since a while we have thought to offer an out-of-the-box solution for this, and these past month we had the time to implement it as a plugin. Enter RabbitMQ Delayed Message Plugin.