The documentation for the ‘cache’ parameter of ‘ajax’ says: > It works by appending "_={timestamp}" to the GET parameters. This seems a bit misleading. I interpreted it as a timestamp of when the request is sent. But the value after `_=` is actually taken from a counter: https://github.com/jquery/jquery/blob/f79d5f1a337528940ab7029d4f8bbba72326f269/dist/jquery.js#L9435 The counter is only initialized using `Date.now()`: https://github.com/jquery/jquery/blob/f79d5f1a337528940ab7029d4f8bbba72326f269/dist/jquery.js#L8501 I got confused by that when analyzing nginx access logs and wondering why the ‘timestamps’ didn’t match up. The documentation should probably just say that it works by appending "_={uid}".