microsoft/ApplicationInsights-dotnet-server#1222 added new module to collect EventCounters.

This repo should make use of it, and start configuring it automatically for .NET Core 3.0 or above. The default list is:

System.Runtime

{ Name="cpu-usage", Description="Amount of time the process has utilized the CPU (ms)", DisplayName="CPU Usage (%)" }
{ Name="working-set", Description="Amount of working set used by the process (MB)", DisplayName="Working Set (MB)" }
{ Name="gc-heap-size", Description="Total heap size reported by the GC (MB)", DisplayName="GC Heap Size (MB)" }
{ Name="gen-0-gc-count", Description="Number of Gen 0 GCs / sec", DisplayName="Gen 0 GC / sec" }
{ Name="gen-1-gc-count", Description="Number of Gen 1 GCs / sec", DisplayName="Gen 1 GC / sec" }
{ Name="gen-2-gc-count", Description="Number of Gen 2 GCs / sec", DisplayName="Gen 2 GC / sec" }
{ Name="time-in-gc", Description="% time in GC since the last GC", DisplayName="% Time in GC (since last GC)" }
{ Name="gen-0-size", Description="Gen 0 Heap Size", DisplayName="Gen 0 Size (B)" }
{ Name="gen-1-size", Description="Gen 1 Heap Size", DisplayName="Gen 1 Size (B)" }
{ Name="gen-2-size", Description="Gen 2 Heap Size", DisplayName="Gen 2 Size (B)" }
{ Name="loh-size", Description="LOH Heap Size", DisplayName="LOH Size (B)" }
{ Name="alloc-rate", Description="Allocation Rate", DisplayName="Allocation Rate (Bytes / sec)" }
{ Name="assembly-count", Description="Number of Assemblies Loaded", DisplayName="# of Assemblies Loaded" }
{ Name="exception-count", Description="Number of Exceptions / sec", DisplayName="Exceptions / sec" }
{ Name="threadpool-thread-count", Description="Number of ThreadPool Threads", DisplayName="ThreadPool Threads Count" }
{ Name="monitor-lock-contention-count", Description="Monitor Lock Contention Count", DisplayName="Monitor Lock Contention Count / sec" }
{ Name="threadpool-queue-length", Description="ThreadPool Work Items Queue Length", DisplayName="ThreadPool Queue Length" }
{ Name="threadpool-completed-items-count", Description="ThreadPool Completed Work Items Count", DisplayName="ThreadPool Completed Work Items / sec" }
{ Name="active-timer-count", Description="Active Timers Count", DisplayName="Number of Active Timers" }

Microsoft.AspNetCore

{ Name="requests-per-second", Description="" }
{ Name="total-requests", Description="" }
{ Name="current-requests", Description="" }
{ Name="failed-requests", Description="Number of requests where HTTP Status Code is >= 500" }