TestFirstMethodCall.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class EventCallPerformanceTest : MonoBehaviour {

    private System.Diagnostics.Stopwatch _stopwatch;

	void Start () {
		
        _stopwatch = new System.Diagnostics.Stopwatch();

        _stopwatch.Restart();
        Debug.Log(_stopwatch.Elapsed.TotalMilliseconds);
        _stopwatch.Stop();

        _stopwatch.Restart();
        Debug.Log(_stopwatch.Elapsed.TotalMilliseconds);
        _stopwatch.Stop();
        
        _stopwatch.Restart();
        EmptyMethod();
        Debug.Log(_stopwatch.Elapsed.TotalMilliseconds);
        _stopwatch.Stop();

        _stopwatch.Restart();
        EmptyMethod();
        Debug.Log(_stopwatch.Elapsed.TotalMilliseconds);
        _stopwatch.Stop();

        _stopwatch.Restart();
        EmptyMethod();
        Debug.Log(_stopwatch.Elapsed.TotalMilliseconds);
        _stopwatch.Stop();        
	}

    private void EmptyMethod() {
    }
}