• Microsoft.ApplicationInsights 2.21.0
• Runtime version: net462
• Hosting environment: Windows - IIS

To Reproduce

We have 30+ ASP.NET Framework apps running on the same IIS.
Only one app has ApplicationInsights enabled, other apps have no connection string at all.
We use performanceCounters - "Private Bytes" to monitor memory consumption by the App.
At some point AppInsights integration starts sending wrong value to the Azure, value from another w3wp process, e.g. metrics logs with instance: w3wp#34, but this w3wp process is from another application pool (identified by Performance Monitor).
after stopping all applications besides that one with enabled ApplicationInsights value is backed to right value (same as in Task Manager for this process)
Looks like there is a bug in identifying right perf counter for running process inside Microsoft.ApplicationInsights.PerfCounterCollector