The Load Balancer dispatches tasks to Integration Service processes running on nodes. When you run a workflow, the Load Balancer dispatches the Session, Command, and predefined Event-Wait tasks within the workflow. If the Integration Service is configured to check resources, the Load Balancer matches task requirements with resource availability to identify the best node to run a task. It may dispatch tasks to a single node or across nodes.
To identify the nodes that can run a task, the Load Balancer matches the resources required by the task with the resources available on each node. It dispatches tasks in the order it receives them. When the Load Balancer has more Session and Command tasks to dispatch than the Integration Service can run at the time, the Load Balancer places the tasks in the dispatch queue. When nodes become available, the Load Balancer dispatches the waiting tasks from the queue in the order determined by the workflow service level.
You assign resources and service levels using the Workflow Manager. You can perform the following tasks:
Assign service levels.
You assign service levels to workflows. Service levels establish priority among workflow tasks that are waiting to be dispatched.
You assign resources to tasks. Session, Command, and predefined Event-Wait tasks require PowerCenter resources to succeed. If the Integration Service is configured to check resources, the Load Balancer dispatches these tasks to nodes where the resources are available.