The simplest way to get more performance from our database is to increase the instance size of our RDS instance; this can be done with very little effort in RDS as we are able to initiate an instance resize from the management console, CLI, or SDK. Once initiated, the instance is shut down and the instance type is changed; this is essentially done in the same way as with EC2 instances. For a single instance RDS, this means that the service will see a disruption as the instance needs to be shut down. In a Multi-AZ deployment, the secondary instance will be resized first, then the traffic will be redirected to the secondary while the master instance is resized.
With an Aurora cluster, the instance replicas are replaced with larger ones and one of the larger instances is promoted to primary, while the smaller instances are shut down. With highly available...