As implemented in the Metasys system, RabbitMQ supports trending and Site Management Portal UI navigation tree features. The Site Director queue receives trend data and navigation tree changes from other system devices. When the Site Director is busy, the messages remain in the queue until the Site Director is available to process them. Using RabbitMQ allows the system to avoid bottlenecks by separating the actions of receiving and processing data. All message queuing functions happen within the server itself; no messages from RabbitMQ broadcast over the network between the server and other devices.
Metasys installs RabbitMQ on all computers where ADS, ADX, or OAS software is installed. Once installed, do not stop, disable, or uninstall RabbitMQ. If RabbitMQ is stopped, disabled, or uninstalled, the Site Director does not receive or process messages. Lost trending data may be irrecoverable. The queue fills at a rate determined by your site configuration and system use; for example, trend frequency or number of additions, changes, or deletions made to the navigation tree.