<PackageReference Include="OpenTelemetry" Version="1.11.2" />

OpenTelemetry.Internal.SelfDiagnostics

sealed class SelfDiagnostics : IDisposable
Self diagnostics class captures the EventSource events sent by OpenTelemetry modules and writes them to local file for internal troubleshooting.
public static void EnsureInitialized()

No member of SelfDiagnostics class is explicitly called when an EventSource class, say OpenTelemetryApiEventSource, is invoked to send an event. To trigger CLR to initialize static fields and static constructors of SelfDiagnostics, call EnsureInitialized method before any EventSource event is sent.

public void Dispose()