Fix bad config type of long_gc (#2504)

etc/emqx.conf

@@ -2222,19 +2222,43 @@ broker.route_batch_clean = off
 ## System Monitor
 ##--------------------------------------------------------------------
 
-## Enable Long GC monitoring.
+## Enable Long GC monitoring. Disable if the value is 0.
 ## Notice: don't enable the monitor in production for:
 ## https://github.com/erlang/otp/blob/feb45017da36be78d4c5784d758ede619fa7bfd3/erts/emulator/beam/erl_gc.c#L421
 ##
-## Value: true | false
+## Value: Duration
-sysmon.long_gc = false
+##  - h: hour
+##  - m: minute
+##  - s: second
+##  - ms: milliseconds
+##
+## Examples:
+##  - 2h:  2 hours
+##  - 30m: 30 minutes
+##  - 0.1s: 0.1 seconds
+##  - 100ms : 100 milliseconds
+##
+## Default: 0ms
+sysmon.long_gc = 0
 
 ## Enable Long Schedule(ms) monitoring.
 ##
 ## See: http://erlang.org/doc/man/erlang.html#system_monitor-2
 ##
-## Value: Number
+## Value: Duration
-sysmon.long_schedule = 240
+##  - h: hour
+##  - m: minute
+##  - s: second
+##  - ms: milliseconds
+##
+## Examples:
+##  - 2h:  2 hours
+##  - 30m: 30 minutes
+##  - 0.1s: 0.1 seconds
+##  - 100ms: 100 milliseconds
+##
+## Default: 0ms
+sysmon.long_schedule = 240ms
 
 ## Enable Large Heap monitoring.
 ##

priv/emqx.schema

@@ -2074,14 +2074,14 @@ end}.
 %% @doc Long GC, don't monitor in production mode for:
 %% https://github.com/erlang/otp/blob/feb45017da36be78d4c5784d758ede619fa7bfd3/erts/emulator/beam/erl_gc.c#L421
 {mapping, "sysmon.long_gc", "emqx.sysmon", [
-  {default, false},
+  {default, 0},
-  {datatype, {enum, [true, false]}}
+  {datatype, [integer, {duration, ms}]}
 ]}.
 
 %% @doc Long Schedule(ms)
 {mapping, "sysmon.long_schedule", "emqx.sysmon", [
-  {default, 1000},
+  {default, 240},
-  {datatype, integer}
+  {datatype, [integer, {duration, ms}]}
 ]}.
 
 %% @doc Large Heap

src/emqx_sys_mon.erl

@@ -33,9 +33,9 @@
         , code_change/3
         ]).
 
--type(option() :: {long_gc, false | pos_integer()}
+-type(option() :: {long_gc, non_neg_integer()}
-                | {long_schedule, false | pos_integer()}
+                | {long_schedule, non_neg_integer()}
-                | {large_heap, pos_integer()}
+                | {large_heap, non_neg_integer()}
                 | {busy_port, boolean()}
                 | {busy_dist_port, boolean()}).
 
@@ -66,11 +66,11 @@ parse_opt(Opts) ->
     parse_opt(Opts, []).
 parse_opt([], Acc) ->
     Acc;
-parse_opt([{long_gc, false}|Opts], Acc) ->
+parse_opt([{long_gc, 0}|Opts], Acc) ->
     parse_opt(Opts, Acc);
 parse_opt([{long_gc, Ms}|Opts], Acc) when is_integer(Ms) ->
     parse_opt(Opts, [{long_gc, Ms}|Acc]);
-parse_opt([{long_schedule, false}|Opts], Acc) ->
+parse_opt([{long_schedule, 0}|Opts], Acc) ->
     parse_opt(Opts, Acc);
 parse_opt([{long_schedule, Ms}|Opts], Acc) when is_integer(Ms) ->
     parse_opt(Opts, [{long_schedule, Ms}|Acc]);
@@ -177,4 +177,3 @@ safe_publish(Event, WarnMsg) ->
 sysmon_msg(Topic, Payload) ->
     Msg = emqx_message:make(?SYSMON, Topic, Payload),
     emqx_message:set_flag(sys, Msg).
-