AWS Graviton Migration Playbook: 40% Compute Savings, Zero Downtime

AWS Graviton (ARM-based EC2) routinely delivers 30–40% better price/performance vs. x86 for typical web/API workloads. Yet most enterprises we audit have less than 10% of their fleet on Graviton.

This is the playbook we use to migrate without downtime.

The 6-Step Migration Playbook

Multi-arch Dockerfile Pattern

# syntax=docker/dockerfile:1.7
FROM --platform=$BUILDPLATFORM node:20-alpine AS build
WORKDIR /app
COPY package*.json ./
RUN npm ci --omit=dev
COPY . .
RUN npm run build

FROM node:20-alpine
WORKDIR /app
COPY --from=build /app/dist ./dist
COPY --from=build /app/node_modules ./node_modules
EXPOSE 3000
CMD ["node", "dist/server.js"]

Terraform — Mixed-instance ASG

resource "aws_autoscaling_group" "web" {
  name             = "web-asg"
  vpc_zone_identifier = var.private_subnets
  min_size            = 4
  max_size            = 40
  desired_capacity    = 8

  mixed_instances_policy {
    instances_distribution {
      on_demand_base_capacity                  = 2
      on_demand_percentage_above_base_capacity = 0
      spot_allocation_strategy                 = "price-capacity-optimized"
    }
    launch_template {
      launch_template_specification {
        launch_template_id = aws_launch_template.web_arm.id
        version            = "$Latest"
      }
      override { instance_type = "m7g.large" }
      override { instance_type = "m6g.large" }
      override { instance_type = "c7g.large" }
    }
  }
}