Over-Provisioned EC2 Worker Fleet (c6i.4xlarge → c6i.2xlarge)
Assumptions: Calculated using us-east-1 On-Demand list prices ($0.680/hr for c6i.4xlarge vs $0.340/hr for c6i.2xlarge). Applied a conservative 21.4% ($212.80/mo) buffer to account for potential scale-out bursts during month-end batch processing.
4x c6i.4xlarge On-Demand instances (16 vCPU, 32 GiB RAM each) running background asynchronous processing workers 24/7. Current combined compute cost: $3,856/month.
Update the Auto Scaling launch template to use c6i.2xlarge (8 vCPU, 16 GiB RAM). Execute a phased instance refresh with 50% minimum healthy percentage during normal operational hours.
- Deploy launch template update to staging worker cluster and simulate 2x peak queue ingestion.
- Verify worker processing latency and message queue depth metrics in Amazon SQS remain within SLA.
- Trigger Canary instance refresh in production (replacing 1 node initially) and monitor CloudWatch CPU/memory metrics for 24 hours.
- Complete rolling deployment across remaining worker nodes.