Cloud Cost Optimization

How do you approach cloud cost optimization? What strategies and tools would you use?

Cloudadvanced

// interview question

How do you approach cloud cost optimization? What strategies and tools would you use?

Sample answer

Cost optimization starts with visibility: use cloud-native tools (AWS Cost Explorer, Azure Cost Management) and third-party solutions (Kubecost, Infracost) to understand spending. Key strategies: 1) Right-sizing - match instance sizes to actual usage. 2) Reserved instances/savings plans for predictable workloads (30-70% savings). 3) Spot/preemptible instances for fault-tolerant workloads. 4) Auto-scaling to match demand. 5) Storage lifecycle policies to move cold data to cheaper tiers. 6) Clean up unused resources (orphaned volumes, old snapshots). 7) Tag everything for cost allocation. Implement FinOps practices with regular cost reviews and accountability.

Why this matters

Cloud costs can spiral out of control without proper governance. Senior engineers must balance performance and reliability requirements with cost efficiency. This directly impacts company profitability and is increasingly a key engineering responsibility.

Code examples

Find unused AWS resources

bash

# Find unattached EBS volumes
aws ec2 describe-volumes \
  --filters Name=status,Values=available \
  --query 'Volumes[*].[VolumeId,Size,CreateTime]'

# Find old snapshots (>90 days)
aws ec2 describe-snapshots --owner-ids self \
  --query 'Snapshots[?StartTime<=`2024-01-01`].[SnapshotId,VolumeSize]'

# Find stopped instances
aws ec2 describe-instances \
  --filters Name=instance-state-name,Values=stopped \
  --query 'Reservations[].Instances[].[InstanceId,InstanceType]'