Can autoscaling jobs in postgres RDS cause performance issues?

Hello, I believe you are using AWS Aurora RDS storage autoscaling. https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/Aurora.Integrating.AutoScaling.html

When you have increased the RDS DB instance's storage using autoscaling, additional storage increases in increments of whichever of the following is greater: 5GB 10% of currently allocated space Storage growth prediction for 7 hours based on the FreeStorageSpace metrics for the past hour

However, if you expect to load 50 GB of data in less than one hour, then the 10% storage increase won't be sufficient. Because the previous autoscaling operation is in the storage-optimization period, the RDS DB instance can't have any storage modifications until the process completes. This might result in an RDS DB instance that is in a storage-full status for up to several hours.

I activated storage autoscaling for my Amazon Relational Database Service (Amazon RDS) DB instance, but I see that the free storage space is below 10% or that the instance is in a storage-full state. Why is this happening, and how can I fix this? Short description

If you changed the RDS DB instance’s storage, you can’t make further modifications for six (6) hours, or until the storage-optimization process has completed. The storage modification period usually takes a few seconds to complete and takes effect after the volume has transitioned to the optimizing state. Sometimes storage-optimization can take more than 24 hours for a new configuration to take effect, such as when the volume has not been fully initialized. For more information about the storage process, see Monitor the progress of volume modifications.

During the storage modification storage-optimization period, autoscaling can't increase your DB instance's storage, even if there's less than 10% of free storage space. For more information, see Increasing DB instance storage capacity.

When you have increased the RDS DB instance's storage using autoscaling, additional storage increases in increments of whichever of the following is greater:

5GB
10% of currently allocated space
Storage growth prediction for 7 hours based on the FreeStorageSpace metrics for the past hour

However, if you expect to load 50 GB of data in less than one hour, then the 10% storage increase won't be sufficient. Because the previous autoscaling operation is in the storage-optimization period, the RDS DB instance can't have any storage modifications until the process completes. This might result in an RDS DB instance that is in a storage-full status for up to several hours. Resolution

If you can't modify the storage of your RDS DB instance, check the following to identify if your instance is affected by the storage-optimization period:

The status of your RDS DB instance is storage-optimization
The status of your RDS DB instance is storage-full or available, but there was a recent storage modification. To confirm that a storage increase operation was recently performed, check your RDS DB instance's events for the following messages:
"Finished applying modification to allocated storage"
-or-
"Finished applying autoscale initiated modification to allocated storage"

If the RDS DB instance isn't in a storage-full state, you can use the following options to modify your DB instance storage size:

Option 1: Create and promote a read replica of your RDS DB instance
Option 2: Take a manual DB snapshot and restore your RDS DB instance to a point in time
Option 3: Autoscaling is turned on but you don't want it to activate due to low FreeStorageSpace

also refer this for further discussion. https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_PIOPS.StorageTypes.html

Thanks.

I believe that this is a RDS Postgres instance and the auto scaling here refers to increasing the allocated storage to prevent running out of available storage. And, no, this operation does not cause performance issues.