Which changes should be made to the database tier to improve performance?
Migrate the database to Amazon RDS for MySQL. Configure Multi-AZ in one of the European Regions.
Migrate the database to Amazon DynamoDB. Use DynamoDB global tables to enable replication to additional Regions.
Deploy MySQL instances in each Region. Deploy an Application Load Balancer in front of MySQL to reduce the load on the primary instance.
Migrate the database to an Amazon Aurora global database in MySQL compatibility mode. Configure read replicas in one of the European Regions.
Explanations:
While migrating to Amazon RDS for MySQL and configuring Multi-AZ improves availability and fault tolerance, it does not directly address the performance issue for European users since the database would still be located in the US.
Migrating to Amazon DynamoDB and using global tables may enhance performance for specific use cases but involves a significant architectural change and may not be suitable for all SQL workloads, particularly those dependent on complex queries.
Deploying MySQL instances in each Region with an Application Load Balancer does not resolve the fundamental issue of latency for European users since they would still be querying the US database, leading to potential performance bottlenecks.
Migrating to an Amazon Aurora global database in MySQL compatibility mode allows for low-latency access for European users by enabling read replicas in Europe, thus significantly improving query performance for that region.
I classify that the answer is:
Migrate the database to an Amazon Aurora global database in MySQL compatibility mode. Configure read replicas in one of the European Regions.