private static function _checkConfig()
{
if (empty(self::$retry_times)) {
self::$retry_times = 0;
}
if (empty(self::$timeout)) {
self::$timeout = 1000;
}
if (empty(self::$c_timeout)) {
self::$c_timeout = self::$timeout;
}
if (empty(self::$r_timeout)) {
self::$r_timeout = 1000;
}
if (empty(self::$w_timeout)) {
self::$w_timeout = 1000;
}
}