title: How should I track down PHP Warning: Input variables exceeded 1000
body: <p>I have a relatively high traffic site, that about once per day generates the error message:</p>
  
  <blockquote>
    <p>PHP Warning:  Unknown: Input variables exceeded 1000. To increase the limit change max_input_vars in php.ini. in Unknown on line 0</p>
  </blockquote>
  
  <p>My guess is that it is caused by some crawler that has found a URL link structure that never ends.  However, I couldn't find any thing in the access logs that would be a problem (e.g. a url with a 1000+ get parameters).</p>
  
  <p>It there an easy way to get insight into this Warning?  It happens before any php scripts are loaded, so I assume it is impossible to introspect with php.  If I had simple details such as the URL, it would be easy to solve.</p>