TLDR: Pre-provision min_provisioned_concurrency ≥ your peak parallel requests (in multiples of 4) with scale-to-zero disabled, and chunk large PDFs in your model code to bound per-request latency — reactive autoscaling can't help CPU-bound workloads that spike faster than new replicas can warm up.

https://docs.databricks.com/aws/en/machine-learning/model-serving/production-optimization