AWS Lambda 推出了 Provisioned Concurrency，降低冷啟動所需要的時間以確保效率：「New – Provisioned Concurrency for Lambda Functions」。
看 benchmark 的資料就很清楚，可以避免冷啟動所產生的延遲：
這邊也可以看出來就算是冷啟動，大約也是多個一秒多。如果這個延遲是需要被處理的，就可以考慮用 Provisioned Concurrency 了。
價位上是依照保留的量：
You only pay for the amount of concurrency that you configure and for the period of time that you configure it. Pricing in US East (N. Virginia) is $0.015 per GB-hour for Provisioned Concurrency and $0.035 per GB-hour for Duration. The number of requests is charged at the same rate as normal functions. You can find more information in the Lambda pricing page.
不過如果量再更大，而且考慮成本，應該會考慮改回傳統的架構，用多台 EC2 instance 跑...