Viewing YARN queues

The YARN Queue Manager is the queue management graphical user interface for the Apache Hadoop YARN Capacity Scheduler. You can use the YARN Queue Manager UI to manage your cluster capacity using queues to balance resource requirements of multiple applications from various users.

Click View YARN Queues on the CDP One console to access the YARN Queue Manager UI.

You can use the the YARN Queue Manager to view, sort, search, and filter queues. Queue Manager stores the history of previous changes and provides the ability to view the changes of each version in the Overview and Scheduler Configuration tabs. Previous versions are in read-only mode.

The fundamental unit of resource allocation in YARN is a queue. The capacity of each queue specifies the percentage of cluster resources that are available for applications submitted to the queue. Capacity Scheduler queues can be set up in a hierarchy that reflects the database structure, resource requirements, and access restrictions required by the various organizations, groups, and users that utilize cluster resources.

For example, suppose that a company has three organizations: Engineering, Support, and Marketing. The Engineering organization has two sub-teams: Development and QA. The Support organization has two sub-teams: Training and Services. And finally, the Marketing organization is divided into Sales and Advertising. The following image shows the queue hierarchy for this example:

Each child queue is tied to its parent queue and the top-level "support", "engineering", and "marketing" queues would be tied to the "root" queue.