Run the main event loop for collector thread.

        In each round the collector traverse the results log directory
        and reload trial information from the status files.

def run(self):
        """Run the main event loop for collector thread.

        In each round the collector traverse the results log directory
        and reload trial information from the status files.
        """
        self._initialize()

        self._do_collect()
        while not self._is_finished:
            time.sleep(self._reload_interval)
            self._do_collect()

        self.logger.info("Collector stopped.")