Something

  def read_log 
    begin 
      log_file = "#{LOG_PATH}/log"
      start_time = Time.now.utc
      Thread.current['active'] = true
      
      tree_path = []
       
      open("| tail -n 0 -f #{log_file}") do |log|
        while Thread.current['active']
          line = log.gets
       
          ...

          LOGGER.info(". ")
          sleep(0.25)              
        end
      end
    rescue
      LOGGER.info("TRACKER ERROR: #{$!}")
    ensure
      LOGGER.info(path)
    end  
  end


  thr = Thread.new {read_log}

  while check
    ...
  end

  thr['active'] = false
  thr.join