You tune the performance of Oracle Database on Oracle Database Cloud Service using the same tools you would use for an Oracle database running on any system in your data center. Database Cloud Service does not place any special restrictions on performance tuning.
The Oracle Database Performance Tuning Guide for Release 18, 12.2, 12.1 or 11.2 provides extensive information about how to use Oracle Database performance tools to optimize database performance. It also describes performance best practices and includes performance-related reference information.
Additionally, the Enterprise Manager Tuning and Performance option packs are included in database deployments created using the High Performance and Extreme Performance software editions. These option packs provide several utilities to assist in maintaining performance and identifying and correcting performance issues.
If your performance tuning activities indicate that you need more computing power or more storage, you can scale Database Cloud Service to satisfy the need. See Scaling a Database Deployment.