Does the consumption plan of Azure Functions support concurrent processing and automatic scaling

Question

Does the consumption plan of Azure Functions support concurrent processing and automatic scaling of the number of instances? If it supports how to check the current number of instances, the number of instances I see in the App Service plan is always 0.

Answer 1

Hello @単ルイ(Shan Rui)

When a function app is using the Consumption hosting plan, the function app could scale out automatically. Each instance of the function app, whether the app runs on the Consumption hosting plan or a regular App Service hosting plan, might process concurrent function invocations in parallel using multiple threads. The maximum number of concurrent function invocations in each function app instance varies based on the type of trigger being used as well as the resources used by other functions within the function app.

The Consumption plan scales automatically, even during periods of high load. When running functions in a Consumption plan, you're charged for compute resources only when your functions are running. On a Consumption plan, a function execution times out after a configurable period of time.
https://learn.microsoft.com/en-us/azure/azure-functions/consumption-plan

On the Consumption plan, instances of the Functions host are dynamically added and removed based on the number of incoming events.
https://learn.microsoft.com/en-us/azure/azure-functions/functions-scale

If you want to see instance scale over time, please go to Azure Function Logs

https://www.adathedev.co.uk/2022/01/monitoring-consumption-plan-instance-scaleout.html