Explanation
Auto scaling is enabled by default when you create an Autonomous Database instance or you can use Scale Up/Down on the Oracle Cloud Infrastructure console to enable or disable auto scaling.
With auto scaling enabled the database can use up to three times more CPU and IO resources than specified by the number of OCPUs currently shown in the Scale Up/Down dialog. When auto scaling is enabled, if your workload requires additional CPU and IO resources the database automatically uses the resources without any manual intervention required.
Enabling auto scaling does not change the concurrency and parallelism settings for the predefined services IO throughput depends on the number of CPUs you provision and scales linearly with the number of CPUs.