We are about to develop a microservice architecture with azure functions inside azure. We thought about using interservice communication with durable functions. 
On app site we want to use an async pub/sub pattern to publish request/commands through a single function gateway. This command will be forwarded to other durable functions and processed there. The response to app will be responded asynchronously via signalR.

All data that need to be processed inside not stateless services will be send via EventGrid/EventHub to the specific cloud services via streaming.

The performance of the durable functions for a roundtrip (App-Functions-App) is about 300 ms. Does anyone has some ideas how to improve the performance?

[![Architecture Overview](https://i.stack.imgur.com/cHeeI.png)](https://i.stack.imgur.com/cHeeI.png)