simple javascript ajax with exponential backoff (untested)

gistfile1.txt

var timeout = {
  initial: 10, // start backoff
  backoff: 1.5, // backoff exponent
  max: 5000, // maximum retry backoff
  fail: ( 1000 * 60 * 3 ), // stop retrying after this time
  loop: 0, // current number of tries
};
function getUrl( url ) {

  if ( ! timeout.start )
    timeout.start = +new Date();

  $.ajax({
    method: "GET",
    url: data_url,
    success: function( response ) {

    },
    error: function( error ){

      if ( ( +new Date - timeout.start ) > timeout.fail )
        return handleGetUrlError( error );

      var timeout = Math.min( Math.pow( ( ++timeout.loop * initial ), 2 ), timeout.max );
      setTimeout( function() {
        getUrl( url );
      }, timeout );
    }
  });
}

function handleGetUrlError( error ) {
  console.error( error )
}