kienbui1995/cloud-cost-review

Cloud Cost Review

When to Use

When cloud bills are growing faster than expected, before quarterly planning, or as a regular monthly hygiene practice.

Core Jobs

1. Understand the Bill

Break down by:

• Service (EC2, RDS, S3, data transfer, etc.)
• Team/project (via tags)
• Environment (prod vs dev vs staging)
• Region

Tools: AWS Cost Explorer, GCP Billing, Azure Cost Management

2. Find Quick Wins

Idle Resources (high impact, easy):

• Instances with CPU < 5% for 14+ days
• Unattached EBS volumes
• Load balancers with no traffic
• Old snapshots (> 90 days)
• Unused Elastic IPs

Rightsizing (medium effort):

• Oversized instances: P95 CPU < 30% → downsize one tier
• Tool: AWS Compute Optimizer, GCP Recommender

Reserved Instances / Savings Plans:

• Workloads running > 8 months/year → commit for 30–40% savings
• 1-year no-upfront = best flexibility vs savings balance

Data Transfer:

• Same-region between services: often free
• Cross-region / egress: expensive — co-locate services
• S3 to EC2 in same region: free

3. Tag Everything

Without tags, you can't attribute costs. Enforce:

• project, team, environment, owner
• Budget alerts per tag value

4. Set Budgets and Alerts

• Monthly budget per service and team
• Alert at 80% and 100% of budget
• Anomaly detection for sudden spikes

Key Outputs

• Cost breakdown report (service + team + env)
• Top 10 optimization opportunities with estimated savings
• Reserved instance / savings plan recommendation
• Tagging compliance report

Anti-Patterns

• Reviewing costs quarterly instead of monthly (surprise bills)
• No tagging → can't attribute costs
• Optimizing dev environments instead of prod (wrong ROI)
• Buying reserved instances for workloads that scale down seasonally