Question

A financial services company runs a customer-facing API backed by AWS Lambda functions accessed through Amazon API Gateway. During business hours, traffic is steady but users report intermittent response times above 3 seconds on the first requests to certain functions after periods of inactivity, while subsequent requests are fast. The functions are written in Java and initialize several large SDK clients at startup. The team needs to eliminate these latency spikes for a predictable set of high-priority functions with minimal code changes. What is the MOST effective solution?

Accepted Answer

Enable Lambda provisioned concurrency on the high-priority functions to keep initialized execution environments ready to respond.

Answer

Increase the memory allocation of the functions to the maximum to reduce initialization time.

Answer

Migrate the functions to Amazon ECS on Fargate to avoid Lambda invocation limits.

Answer

Add an Amazon ElastiCache for Redis cluster in front of the functions to cache API responses.