sys:statistics/2
允许或禁止收集统计数据
用法：
statistics(Name, Flag) -> ok | {ok, Statistics}
允许或禁止收集统计数据。
参数 Flag 的取值有：
- true：允许收集统计
- get：获取收集的统计信息
- false：禁止收集统计
RegisteredList = erlang:registered(), RegisteredListLen = length(RegisteredList), random:seed(erlang:now()), Rand = random:uniform(RegisteredListLen), RegisterName = lists:nth(Rand, RegisteredList), sys:statistics(RegisterName, true).
RegisteredList = erlang:registered(), RegisteredListLen = length(RegisteredList), random:seed(erlang:now()), Rand = random:uniform(RegisteredListLen), RegisterName = lists:nth(Rand, RegisteredList), sys:statistics(RegisterName, get).
RegisteredList = erlang:registered(), RegisteredListLen = length(RegisteredList), random:seed(erlang:now()), Rand = random:uniform(RegisteredListLen), RegisterName = lists:nth(Rand, RegisteredList), sys:statistics(RegisterName, false).