PHP performance issues are quite challenging to troubleshoot as we don't have any in-built tools that comes with IIS. We could use tools like Windows Debugging tools, Debug Diagnostic or Perfview for any slow response for an applications running in IIS. However for PHP application this may not be helpful.
This Video helps in using various tools like PHP profiler X-debug and WinCacheGrind on troubleshoot slow response issues for PHP application. For this session I'm creating a simple php page named Display.php and time.php that takes 10 seconds to execute. Following is the code snippet
echo "<br />";