after.php

<?php
$response = new StdClass();
$response->body = new StdClass();
$response->body->foo = "bar";
$response->headers = new StdClass();
$response->headers->Etag = "\"asdfasfsadfsadf\"";

$cache = new SagMemoryCache();

sample();

for($i = 1; $i &lt;= 100000; $i++)
  $cache->set("$i", $response);

sample();
?>

before.php

<?php
$sag->setCache(new SagMemoryCache());
$response = $sag->get($url);
$response->body->name= "Joe"; //shouldn't update cached response
?>