docs: def update_fileserver(self, interval, backends):
          '''
          Threading target which handles all updates for a given wait interval
          '''
          def _do_update():
              log.debug(
                  'Performing fileserver updates for items with an update '
                  'interval of %d', interval
              )
              for backend, update_args in six.iteritems(backends):
                  backend_name, update_func = backend
                  try:
                      if update_args:
                          log.debug(
                              'Updating %s fileserver cache for the following '
                              'targets: %s', backend_name, update_args
                          )
                          args = (update_args,)
                      else:
                          log.debug('Updating %s fileserver cache', backend_name)
                          args = ()
  
                      update_func(*args)
                  except Exception as exc:
                      log.exception(
                          'Uncaught exception while updating %s fileserver '
                          'cache', backend_name
                      )
  
              log.debug(
                  'Completed fileserver updates for items with an update '
                  'interval of %d, waiting %d seconds', interval, interval
              )
  
          condition = threading.Condition()
          _do_update()
          while True:
              with condition:
                  condition.wait(interval)
              _do_update()