In all examples I see the database adapter set as a non-shared service. Like this:
$di->set("db", function() use ($config) {
    return new \Phalcon\Db\Adapter\Pdo\Mysql(array(
         "host" => $config->host,
         "username" => $config->username,
         "password" => $config->password,
         "dbname" => $config->name
    ));
});Wouldn't it be better as a shared service ?