Queues are the primary method used to manage multiple workloads. Queues can provide workload isolation and thus guarantee available capacity for different workloads. This can help different types of workloads meet Service Level Agreements (SLAs).
Within each queue, you can allow one or more sessions to live simultaneously. Sessions cooperatively share the resources of the queue.
For example, a queue that is assigned 10% of cluster resources can get these allocated anywhere in the cluster depending on the query and data placement. Where the resources are allocated may change as more queries are run.
The following figure shows a configuration in which 50% of the cluster capacity is assigned to a “default” queue for batch jobs, along with two queues for interactive Hive queries, with each Hive queue assigned 25% of cluster resources. Two sessions are used in the batch queue, and three sessions are used in each Hive queue.
