When I started my current role, our AWS bill was steadily increasing each month. Leadership was concerned, and rightfully so. Here's how we reversed the trend and achieved sustainable cost savings.
The Initial Assessment
Our first step was conducting a comprehensive audit using AWS Cost Explorer and Trusted Advisor. The findings were eye-opening:
A significant portion of EC2 instances were over-provisionedWe had not yet taken advantage of Reserved Instances or Savings PlansUnattached EBS volumes were incurring unnecessary chargesS3 lifecycle policies were non-existentImplementation Strategy
1. Right-Sizing EC2 InstancesWe deployed CloudWatch agents to collect memory and disk metrics. After a period of data collection, we identified:
Multiple instances running at low CPU utilizationOthers with low memory usageSeveral workloads that could move to burstable T3 typesResult: significant monthly savings by right-sizing
2. Reserved Instances & Savings PlansAnalyzed our steady-state workloads and committed to:
Multi-year Reserved Instances for production databasesCompute Savings Plans for variable workloadsKept some capacity on-demand for flexibilityResult: substantial savings on compute costs
3. Storage OptimizationImplemented S3 lifecycle policies:
Move logs to Glacier after a set periodDelete non-production backups after a fixed retentionEnabled S3 Intelligent-Tiering for uncertain access patternsResult: major reduction in storage costs
4. Automation & GovernanceBuilt Lambda functions to:
Stop non-production instances outside business hoursDelete unattached EBS volumes after a short periodAlert on anomalous spending increasesResult: additional savings and prevented cost creep
Lessons Learned
1. Start with visibility: You can't optimize what you can't measure2. Involve the team: Engineers often know where the waste is3. Automate ruthlessly: Manual cost management doesn't scale4. Review regularly: Cloud costs are not "set and forget" Next Steps
We're now exploring:
Kubernetes cost allocation with KubecostSpot instances for batch workloadsARM-based Graviton instancesThe journey to cost optimization never truly ends, but with the right approach, you can achieve significant, sustainable savings.