anchor.diff:       {[memory], {function, erlang, memory, [], proplist,
                    [total, processes, system,
                     atom, binary, code, ets]}, []},
  +     {[system_stats], {function, ?MODULE, system_statistics, [], proplist,
  +                      system_statistics_items()}, []},
  +     {[cpuinfo], {function, ?MODULE, scheduler_utilization, [], proplist,
  +                 scheduler_utilization_items()}, []},
        {[subscriptions], {function, vmq_reg, total_subscriptions, [], proplist, [total]}, []},
        {[clients], {function, vmq_reg, client_stats, [], proplist,
  -                  [total, active, inactive]}, []}
  +                  [total, active, inactive]}, []},
  +     {[clients, expired], counter, [{snmp, []}]}
        | counter_entries()];
   entries({ReporterMod, Interval}) ->
       subscribe(ReporterMod, entries(undefined), Interval).
  
positive.code:      {[sockets, last_min], counter, [{snmp, []}]},
       {[sockets, last_5min], counter, [{snmp, []}]}
      ].
  
  subscribe(ReporterMod, [{Metric, histogram, _}|Rest], Interval) ->
      Datapoints = [max, min, mean, median],
  
negative.code:          entries/1]).
  
  %% API functions
  -export([start_link/0,
           system_statistics/0,
           scheduler_utilization/0]).
  
  %% gen_server callbacks
  -export([init/1,
  