code: @Override
  	public void setJobRunning(JobID jobID) throws IOException {
  		checkNotNull(jobID, "jobID");
  		final Path filePath = createMarkerFilePath(RUNNING_PREFIX, jobID);
  
  		// create the file
  		// to avoid an exception if the job already exists, set overwrite=true
  		createFile(filePath, true);
  	}
docs: ------------------------------------------------------------------------