$this->srvsByBucket = array_values( $this->srvsByBucket ); // consecutive
$memcConfig = isset( $config['memcConfig'] ) ? $config['memcConfig'] : [];
$this->srvsByBucket = array_values( $this->srvsByBucket ); // consecutive
$memcConfig = isset( $config['memcConfig'] ) ? $config['memcConfig'] : [];