https://docs.microsoft.com/en-us/azure/azure-functions/functions-scale says:
Event driven. Scale out automatically, even during periods of high load. Azure Functions infrastructure scales CPU and memory resources by adding additional instances of the Functions host, based on the number of incoming trigger events.
Do activity functions being called by an orchestrator function count as an "incoming trigger event"?
Such as
yield context.df.callActivity('myActivity', {})
What about an orchestrator function being called by another type of trigger function, such as a queue trigger?
Such as:
const instanceId = await client.startNew('MyOrchestrator", undefined, {});