log/emqttd_sysmon.log

rel/files/emqttd.config.development

@@ -276,6 +276,8 @@
 
     %% Erlang System Monitor
     {sysmon, [
+        %% Log file.
+        {logfile, "log/emqttd_sysmon.log"},
 
         %% Long GC
         {long_gc, 100},

rel/files/emqttd.config.production

@@ -268,6 +268,8 @@
 
     %% Erlang System Monitor
     {sysmon, [
+        %% Log file.
+        {logfile, "log/emqttd_sysmon.log"},
 
         %% Long GC, don't monitor in production mode for:
         %% https://github.com/erlang/otp/blob/feb45017da36be78d4c5784d758ede619fa7bfd3/erts/emulator/beam/erl_gc.c#L421