code: public function flush()
      {
          if ($this->doNotTrack) {
              return;
          }
  
          if (empty($this->queue)) {
              return;
          }
  
          if ($this->mergePackets) {
              $this->send(implode("\n", $this->queue));
          } else {
              foreach ($this->queue as $data) {
                  $this->send($data);
              }
          }
          $this->queue = array();
          $this->queueSize = 0;
      }
docs: Flushes the queue