Kubernetes on GKE: When to Use It and When Cloud Run Is Enough

Kubernetes is powerful. It's also complex, expensive to operate, and often overkill. After running workloads on both GKE and Cloud Run in production, here's how I decide between them.

Cloud Run is the right default for most web services. It handles autoscaling, SSL, custom domains, and deployment with zero cluster management. You give it a container, it runs it. For request-driven workloads. APIs, web apps, webhooks. Cloud Run is almost always the better choice.

GKE starts making sense when you need capabilities Cloud Run doesn't offer. Long-running background workers that need to maintain state. Workloads that require GPUs. Services that need to communicate over a private network with sub-millisecond latency. Complex scheduling requirements. If your workload fits any of these, GKE is worth the operational overhead.

The cost math is counterintuitive. Cloud Run's per-request billing is cheaper for bursty workloads but gets expensive at sustained high traffic. GKE's node-based pricing is more predictable and often cheaper when you have consistent baseline load. I've seen teams save 40% by moving sustained workloads from Cloud Run to GKE with node auto-provisioning.

If you do choose GKE, Autopilot mode is the way to go for most teams. It handles node management, security patching, and resource optimization. You define pods, and Google handles the rest. Standard mode only makes sense when you need specific node configurations or GPUs.

One hybrid pattern I use frequently: Cloud Run for the web-facing API layer, GKE for background processing. The API receives requests and publishes to Pub/Sub, while GKE workers consume messages and handle the heavy lifting. This gives you the simplicity of Cloud Run where it matters most and the power of Kubernetes where you need it.

The team factor is often overlooked. Running GKE well requires Kubernetes expertise, not just deploying pods, but understanding networking, RBAC, resource quotas, pod disruption budgets, and upgrade strategies. If your team doesn't have this expertise, Cloud Run's simplicity is a feature, not a limitation.

My rule of thumb: start with Cloud Run. Migrate to GKE only when you hit a concrete limitation, not a theoretical one.