% my $now = 1;
<div id="test">
 <p> <%= $now %> </p>
 % $now++;
</div>

<script type="text/javascript">
  function autoRefresh_div() {
    $("#test).load(location.href + " #test", function() {
        setTimeout(autoRefresh_div, 3000);
    });
  }
  autoRefresh_div();
</script>