Your instance benefits from a powerful cache system that works with Varnish.
This allows you to distribute the content of your website

This will allow you to distribute the content of your website to a larger number of visitors without using the resources of your instance.

If for some reason you would like to deactivate the cache system on your pages, you must add a the following header: HTTP Cache-Control: public, max-age=1

For example, in php:

header("Cache-Control: max-age=1");

Or in an .htaccess file if it is a static website:

Header add Cache-Control "max-age=1"

Note that the performance of your instance will be reduced without the cache system in place.

It is possible to purge a particular url cache by sending a HTTP PURGE request.

Here is an example:

<?php
/* purge.php
 * Purge an url on this host
 */
header("Cache-Control: max-age=1"); // don't cache ourself
 
error_reporting(E_ALL);
ini_set("display_errors", 1);
 
// Set to true to hide varnish result
define("SILENT", false);
 
$path = isset($_GET["path"]) ? $_GET["path"] : "";
 
$purge_url = "http://" . $_SERVER["HTTP_HOST"] . "/$path";
 
if ( $ch = curl_init($purge_url) ) {
    curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "PURGE");
    curl_setopt($ch, CURLOPT_NOBODY, SILENT);
 
    curl_exec($ch);
    curl_close($ch);
}
?>

Example use : http://1234.betasimple.net/purge.php?path=/page-to-purge