code: @Override
      public void run()
      {
          while (true)
          {
              try
              {
                  Thread.sleep(120000);
                  PeerMonitor.getInstance().startSweep();
              }
              catch (final InterruptedException e)
              {
                  PeerMonitor.logger.error(e, e);
  
              }
          }
  
      }
docs: Runs the mark and sweep operation every 120 seconds on all channels to
  clean up any channels that have died and for which (for some reason) we
  missed the hangup event.