Question How to test performance of image tracking？

Hello ,I need to test the time of ARCore image tracking and performance ,how to do it? I select the time from "update" to "OnTrackedImagesChanged", Is this correct?

Code (CSharp):

1. private void Update()
2. {
3.         updateTime = DateTime.Now;
4. }
5.  
6.  
7.  
8. void OnTrackedImagesChanged(ARTrackedImagesChangedEventArgs eventArgs)
9. {
10.          string t = DateTime.Now.ToString("ss.fffff");
11.          foreach (var trackedImage in eventArgs.added)
12.         {
13.      
14.             Debug.Log($"{trackedImage.referenceImage.name}, start update:{updateTime.ToString("ss.fffff")}, match:{t}");
15.              
16.         }
17.      
18.  }