Setting Runtime Priority for the Resource Pool
For each resource pool, you can manage resources that are assigned to queries that are already running. You assign each resource pool a runtime priority of HIGH, MEDIUM, or LOW. These settings determine the amount of runtime resources (such as CPU and I/O bandwidth) assigned to queries in the resource pool when they run. Queries in a resource pool with a HIGH priority are assigned greater runtime resources than those in resource pools with MEDIUM or LOW runtime priorities.
Prioritizing Queries Within a Resource Pool
While runtime priority helps to manage resources for the resource pool, there may be instances where you want some flexibility within a resource pool. For instance, you may want to ensure that very short queries run at a high priority, while also ensuring that all other queries run at a medium or low priority.
The Resource Manager allows you this flexibility by letting you set a runtime priority threshold for the resource pool. With this threshold, you specify a time limit (in seconds) by which a query must finish before it is assigned the runtime priority of the resource pool. All queries begin running with a HIGH priority; once a query's duration exceeds the time limit specified in the runtime priority threshold, it is assigned the runtime priority of the resource pool.
Setting Runtime Priority and Runtime Priority Threshold