Lambda Managed Instances with Terraform: Multi-Concurrency, High Memory, and Compute Options (opens in new tab)

Lambda has always been one request at a time per execution environment. Your function starts, processes a single invocation, and sits idle until the next one arrives. If you need to handle a thousand concurrent requests, Lambda spins up a thousand execution environments - each with its own memory, its own cold start, and its own per-GB-second bill. Lambda Managed Instances changes that model. Announced at re:Invent 2025 and expanded with 32 GB memory / 16 vCPU support in March 2026, LMI runs ...