Right-sized an over-provisioned Amazon RDS instance supporting a WordPress deployment to reduce cost while maintaining stability.
Overview
This project focused on correcting an over-provisioned Amazon RDS configuration supporting a self-hosted WordPress site running on EC2. The original database instance size exceeded the needs of the workload, creating unnecessary cost without performance benefit.
Architecture
- EC2: t3.small
- RDS: MySQL (db.t3.small)
- Storage: gp2
- Networking: Default VPC, Elastic IP
- Application: WordPress
Problem
The database tier was initially deployed as db.m5.large, which was not aligned with the site’s traffic profile or usage patterns.
Solution
- Reviewed workload characteristics and baseline usage.
- Took a manual snapshot to ensure rollback safety.
- Modified the RDS instance class from db.m5.large → db.t3.small.
- Monitored RDS events and instance health during the change.
- Validated application connectivity post-modification.
- Updated cost estimates using the AWS Pricing Calculator.
Outcome
- Successfully reduced database instance size with no service disruption.
- Maintained full WordPress functionality after the change.
- Lowered monthly infrastructure costs while preserving performance headroom.
Key Takeaway
Right-sizing is not about minimizing resources — it’s about aligning infrastructure with actual workload requirements.
