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}".