Inside Automation Engine > Multi-Server Operation > Process Queues

Process Queues

All queued tasks in the Automation Engine are divided into individual partial steps. The tasks in the individual queues are a result of these partial steps. The server processes read these tasks from the queue and execute them.

Queues are technically realized as tables in the AE databaseA database is an organized collection of data including relevant data structures..

Work Queues

Each AE system has several message queues. Depending on their types, tasks are lined up in the corresponding queue. If a work process is momentarily idle or finished with its current tasks, it will take the next queued task and process it. The execution of the task can lead to a new task for the work queue. This is then attached to the current tasks. Some tasks can only be processed by the primary work process. For this reason, the "freed-up" primary work process always checks first if any of these special work processes are present in the queue. This is then processed by the primary work process before all other tasks. If this task requires the passing of information to agents or UserInterfaces, the work process writes its own task to the respective communication queue.

Further information about message queues can be retrieved using the script function SYS_INFO.

Communication Queue

Each communication process within an AE system possesses its own communication queue. The work processes file all "external" tasks for the agents and UserInterfaces in this queue. The communication process works down the tasks in its queue.