RDS for MySQL series upgrading allows you to upgrade a single instance to a one-master-and-one-slave instance.
Application Scenarios
You can manually upgrade your instance to improve its performance if the existing instance type cannot meet your service requirements.
Prerequisites
The instance status is Running.
The kernel version is up to date.
Affect
The database service will be unavailable when upgrading the instance. It is recommended that you arrange your service reasonably and operate with caution.
Procedure
1. Log in to the Console.
2. Click 
in the upper left corner of the Console, and select Region and Project.
3. Select Database > Relational database... and go to the MySQL Console.
4. On the Instance Management page, select the specified instance, click More to select the Series Upgrading, go to the Series Upgrading page, and upgrade the instance.