Rundown events sent during .NET Core app shutdown are not used to identify methods

[kouvel]

From dotnet/coreclr#27238 (comment)

Repro:

using System;
using System.Runtime.CompilerServices;
using System.Threading;

static class PerfViewTierEventsTest
{
    private static void Main()
    {
        var t = new Thread(Run);
        t.IsBackground = true;
        t.Start();

        Thread.Sleep(2000);
        Console.Write("Enter to stop: ");
        Console.ReadLine();
    }

    [MethodImpl(MethodImplOptions.NoInlining)]
    private static void Run()
    {
        while (true)
            ++s_value;
    }

    private static int s_value;
}

From command prompt:

• set COMPlus_TieredCompilation=0
• Build and run the repro
• After "Enter to stop:" is printed, start profiling in PerfView
• After a few seconds, press enter on the app and wait for it to shut down
• Stop profiling in PerfView

CPU stacks:

Name             	Exc %	   Exc	Inc %	     Inc	Fold	                             When	   First	      Last
?!0x7ffe959f9216 	 93.6	 3,568	 93.7	   3,572	   0	 _69999999999999999990___________	 250.452	 3,858.991

Expected behavior is that the frame with the highest number of samples is correctly named and it is possible to drill into the source code to see sample counts by line.

Event stats:

Name	Count	AverageSize	StackCount
Microsoft-Windows-DotNETRuntimeRundown/Method/DCStopVerbose	68513	337	0
Microsoft-Windows-DotNETRuntimeRundown/Method/ILToNativeMapDCStop	61645	107	0

Although counts are shown for the events, they are not listed in the Events view when PerfView is started with -KeepAllEvents.

Also not sure why there would be so many of these events, looks like the counts may be incorrect as well.