This code works fine for me:
$m = new Memcached();
$m->addServer('127.0.0.1', 11211);
$m->set('key', 'hello world');
var_dump($m->get('key'));
This code works fine for me:
$m = new Memcached();
$m->addServer('127.0.0.1', 11211);
$m->set('key', 'hello world');
var_dump($m->get('key'));