I recently completed an enterprise migration from AWS to GCP. Here are insights that could help others considering a similar move.
Why GCP Won
The deciding factor was dramatic savings on cross-region networking. AWS's inter-region traffic costs were always painful for our distributed systems. GCP's free intra-continent traffic between regions saved us ~30% immediately.
Migration Surprises
1. GCP's Cloud Load Balancing costs significantly less than AWS ALB/NLB, but came with a catch — no support for multiple SSL certificates per load balancer. We had to redesign our routing logic.
2. BigQuery vs Athena: While BigQuery appears more expensive upfront, its performance for complex analytics justified the cost. But migrating DDL scripts required complete rewrites — the syntax differences are radical.
What Stayed on AWS
Despite the migration, we kept some services on AWS:
- CloudFront — GCP's edge locations still can't match the coverage
- RDS for PostgreSQL — GCP's managed service didn't support our required version
Key takeaway: Hybrid cloud isn't a failure — it's a strategic compromise.