Managing queues

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

You can view, sort, search, and filter queues using YARN Queue Manager UI. Queue Manager stores history of previous changes and provides the ability to view the changes of each version in the Overview and Scheduler Configuration tabs. The previous versions will be in the read-only mode and you must select the latest version to make changes.

The fundamental unit of scheduling 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.