anchor.diff:      ["start"] ->
           Threshold = application:get_env(lager, event_watcher_threshold, 1000),
           Interval = application:get_env(lager, event_watcher_interval, 1000),
  -        MarksLen = application:get_env(lager, event_watcher_marks_len, 3),
  +        MaxOverCnt = application:get_env(lager, event_watcher_max_over_cnt, 3),
           RebootAfter = application:get_env(lager, event_watcher_reboot_after, 5000),
   
           Watcher = {lager_event_watcher, {lager_event_watcher, start_link, 
  -                                         [Threshold, Interval, MarksLen, RebootAfter]},
  +                                         [Threshold, Interval, MaxOverCnt, RebootAfter]},
                      permanent, 5000, worker, [lager_event_watcher]},
           
           supervisor:terminate_child(lager_sup, lager_event_watcher),
  
positive.code: %% start: ./erl_expect -sname ejabberd@sdb-ali-hangzhou-ejabberd3 -setcookie 'LTBEXKHWOCIRRSEUNSYS' common/lager_event_watcher.erl start
  %% stop ./erl_expect -sname ejabberd@sdb-ali-hangzhou-ejabberd3 -setcookie 'LTBEXKHWOCIRRSEUNSYS' common/lager_event_watcher.erl stop
  %% get_state ./erl_expect -sname ejabberd@sdb-ali-hangzhou-ejabberd3 -setcookie 'LTBEXKHWOCIRRSEUNSYS' common/lager_event_watcher.erl get_state
  %% set ./erl_expect -sname ejabberd@sdb-ali-hangzhou-ejabberd3 -setcookie 'LTBEXKHWOCIRRSEUNSYS' common/lager_event_watcher.erl threshold|interval|marks_len|reboot_after N
  %% e.g.
  %% ./erl_expect -sname ejabberd@sdb-ali-hangzhou-ejabberd3 -setcookie 'LTBEXKHWOCIRRSEUNSYS' common/lager_event_watcher.erl threshold 1000
  
  
negative.code:         lager_event_watcher:get_state();
      [Key, Value] when Key == "threshold";
                        Key == "interval"
                        Key == "max_over_cnt" 
                        Key == "reboot_after" ->
          try list_to_integer(Value) of
              N ->
  