Session vs（re）包括更快的页面加载

Could someone say what´s the fastest way to load a page content: Reincludind repetitive content on every page loading or storing it as a session?

I want to include a static menu. So it should be required on every page of my website. Would someone recomend require it once and store it as a session to improve the speed for the next pages loadings?

I.e:

Page 1

<?php

require('inc/menu.php'); 

$_SESSION['menu'] = $sMenu;

//content goes here

?>

Page 2, 3 , 4, n...

<?php

if(isset($_SESSION['menu'])){
$sMenu = $_SESSION['menu']
}

else{
require('inc/menu.php'); 
}

//content goes here

?>

Note that the menu is just an example. It could be used for other includes anyway.

Thanks in advance.