auto profiler

code/controllers/configuration/entries/general.dm

@@ -1,3 +1,5 @@
+/datum/config_entry/flag/auto_profile // Automatically start profiler on server start
+
 /datum/config_entry/flag/autoadmin  // if autoadmin is enabled
 	protection = CONFIG_ENTRY_LOCKED
 

code/controllers/subsystem/profiler.dm

@@ -0,0 +1,50 @@
+#define PROFILER_FILENAME "profiler.json"
+
+SUBSYSTEM_DEF(profiler)
+	name = "Profiler"
+	init_order = INIT_ORDER_PROFILER
+	runlevels = RUNLEVELS_DEFAULT | RUNLEVEL_LOBBY
+	wait = 600
+
+/datum/controller/subsystem/profiler/Initialize()
+	if(CONFIG_GET(flag/auto_profile))
+		StartProfiling()
+	else
+		StopProfiling() //Stop the early start from world/New
+	return ..()
+
+/datum/controller/subsystem/profiler/fire()
+	if(CONFIG_GET(flag/auto_profile))
+		DumpFile()
+
+/datum/controller/subsystem/profiler/Shutdown()
+	if(CONFIG_GET(flag/auto_profile))
+		DumpFile()
+	return ..()
+
+/datum/controller/subsystem/profiler/proc/StartProfiling()
+#if DM_BUILD < 1506 || DM_VERSION < 513
+	stack_trace("Auto profiling unsupported on this byond version")
+	CONFIG_SET(flag/auto_profile, FALSE)
+#else
+	world.Profile(PROFILE_START)
+#endif
+
+/datum/controller/subsystem/profiler/proc/StopProfiling()
+#if DM_BUILD >= 1506 && DM_VERSION >= 513
+	world.Profile(PROFILE_STOP)
+#endif
+
+/datum/controller/subsystem/profiler/proc/DumpFile()
+#if DM_BUILD < 1506 || DM_VERSION < 513
+	stack_trace("Auto profiling unsupported on this byond version")
+	CONFIG_SET(flag/auto_profile, FALSE)
+#else
+	var/current_profile_data = world.Profile(PROFILE_REFRESH,format="json")
+	if(!length(current_profile_data)) //Would be nice to have explicit proc to check this
+		stack_trace("Warning, profiling stopped manually before dump.")
+	var/json_file = file("[GLOB.log_directory]/[PROFILER_FILENAME]")
+	if(fexists(json_file))
+		fdel(json_file)
+	WRITE_FILE(json_file, current_profile_data)
+#endif