AWS Certified Database – Specialty — Question 307

A company plans to use AWS Database Migration Service (AWS DMS) to migrate its database from one Amazon EC2 instance to another EC2 instance as a full load task. The company wants the database to be inactive during the migration. The company will use a dms.t3.medium instance to perform the migration and will use the default settings for the migration.
Which solution will MOST improve the performance of the data migration?

Answer options

• A. Increase the number of tables that are loaded in parallel.
• B. Drop all indexes on the source tables.
• C. Change the processing mode from the batch optimized apply option to transactional mode.
• D. Enable Multi-AZ on the target database while the full load task is in progress.

Correct answer: B

Explanation

Dropping indexes on the tables before starting a full load migration significantly improves performance by reducing the write overhead on the target database during data insertion. Increasing parallel loads on a small dms.t3.medium instance can cause resource exhaustion, while transactional mode is slower than the default batch optimized apply mode. Enabling Multi-AZ on the target database would also decrease performance due to the overhead of synchronous replication.