Lambda vs Cloud Functions vs Azure Functions

AWS Lambda, Google Cloud Functions, and Azure Functions are the serverless compute offerings from the three major cloud providers. All let you run code without managing servers, but they differ in resource limits, pricing, and ecosystem integration.

Resource Limits Comparison

Google Cloud Functions 2nd gen leads in resource limits: 60-minute execution time and 32 GB memory, compared to Lambda's 15 minutes and 10 GB. Azure Functions has a 230-second default timeout on the Consumption plan (configurable up to 60 minutes on Premium) and up to 14 GB memory on the Premium plan.

For long-running data processing tasks, Cloud Functions 2nd gen or Azure Functions Premium are better choices. For short, event-driven handlers, Lambda's limits are rarely a constraint.

Pricing Models

All three charge per invocation and for compute time. Lambda is cheapest per invocation at $0.20/million. Cloud Functions charges $0.40/million. Azure Functions charges $0.20/million on the Consumption plan. Compute pricing varies by memory and CPU allocation.

Azure Functions uniquely offers a hosting plan where you run functions on pre-provisioned App Service Plans, trading the serverless pricing model for predictable costs and no cold starts.

Ecosystem Lock-In

Each function platform integrates deeply with its cloud's services. Lambda + API Gateway + DynamoDB + SQS is a common AWS pattern. Cloud Functions + Pub/Sub + Firestore + BigQuery is the GCP equivalent. Azure Functions + Cosmos DB + Event Grid + Service Bus is the Azure pattern.

Choosing a serverless platform is effectively choosing a cloud ecosystem. Understand these patterns for system design interviews. Review our concepts and interview questions. Check pricing for access.