HeatWave uses a workload-aware, priority-based, automated scheduling mechanism to schedule concurrently issued queries for execution. The scheduling mechanism prioritizes short-running queries but considers wait time in the queue so that costlier queries are eventually scheduled for execution. This scheduling approach reduces query execution wait times overall.
When HeatWave is idle, an arriving query is scheduled immediately for execution. It is not queued. A query is queued only if a preceding query is running on HeatWave.
A light-weight cost estimate is performed for each query at query compilation time.
Queries cancelled via
Ctrl-C are removed
from the scheduling queue.
For a query that you can run to view the HeatWave query history including query start time, end time, and wait time in the scheduling queue, see Section 6.2, “HeatWave Monitoring”.