(PECL memcached >= 0.1.0)
Memcached::__construct — Create a Memcached instance
$persistent_id
  ] )Creates a Memcached instance representing the connection to the memcache servers.
persistent_id
       By default the Memcached instances are destroyed at the end of the
       request. To create an instance that persists between requests, use
       persistent_id to specify a unique ID for the
       instance. All instances created with the same
       persistent_id will share the same connection.
      
A Memcached object.
Example #1 Creating a Memcached object
<?php
/* Create a regular instance */
$m = new Memcached();
echo get_class($m);
/* Create a persistent instance */
$m2 = new Memcached('story_pool');
$m3 = new Memcached('story_pool');
/* now $m2 and $m3 share the same connection */
?>