About the IIS site request queue length?

Question

OS: Windows Server 2016 Standard
IIS: Version 10.0.14393.0
Web Sites: WebIISQueueTest .NetFramework4.5 Asp.net mvc

Question 1: By which performance counter does the site's request queue length be monitored?

Question 2: The request queue length is set but can be exceeded, why not return 503.

Performance counters HTTP Service Request Queues (CurrentQueueSize): The request count in the IIS queue on windows server 2016

The CurrentQueueSize property always has a zero value , why ?

application pool img: https://i.stack.imgur.com/k8tsS.png

Answer 1

Microsoft IIS BUG!!! , HTTP Service Request Queues Performance counter

Why do I say there are bug，look at the pictures below, RejectedRequests has values from the monitor. Why CurrentQueueSize the queue have no values?

HTTP Service Request Queues (All instances):
CurrentQueueSize: Allows you to see the size if the HTTP Kernel side queue and thus to see if a huge number of requests are getting queued without being handled by the User Mode side
RejectedRequests: Allows you to see if requests are rejected from Kernel side without being handled by the User Mode side

@Bruce Zhang-MSFT
@Sreeju Nair

Answer 2

Can you set the value with powershell like in this thread?

https://stackoverflow.com/questions/50812016/set-iis-default-app-pool-queue-length-powershell