IIS Tweak Performance Settings
Go to Application Pool and set Maximum Worker Process = 0
When deploying your application make sure to set Compilation Debug = false in Web.Config for speed optimization
Assign IIS Application Pool Identity to LocalSystem so that the Server can have respect for the processes running under the Application Pool.
If your App's Application Pool is running in the Integrated Mode, the MaxConcurrentRequestPerCPU is restricted to only 5000 which is plenty to run an asynchronous number of the request unless if your application has millions of visitors then you should move to a Server with more thread (Dual-Core Processor).
Make sure to Minify your code when deploying the application
Make sure Https/2 is utilized when serving the requests