tgstation/tgstation#64448 (#10208)

code/controllers/subsystem.dm

@@ -20,8 +20,16 @@
 	var/next_fire = 0		//scheduled world.time for next fire()
 	var/cost = 0			//average time to execute
 	var/tick_usage = 0		//average tick usage
-	var/tick_overrun = 0	//average tick overrun
-	var/state = SS_IDLE		//tracks the current state of the ss, running, paused, etc.
+	/// Running average of the amount of tick usage (in percents of a game tick) the subsystem has spent past its allocated time without pausing
+	var/tick_overrun = 0
+
+	/// How much of a tick (in percents of a tick) were we allocated last fire.
+	var/tick_allocation_last = 0
+
+	/// How much of a tick (in percents of a tick) do we get allocated by the mc on avg.
+	var/tick_allocation_avg = 0
+	/// Tracks the current execution state of the subsystem. Used to handle subsystems that sleep in fire so the mc doesn't run them again while they are sleeping
+	var/state = SS_IDLE
 	var/paused_ticks = 0	//ticks this ss is taking to run right now.
 	var/paused_tick_usage	//total tick_usage of all of our runs while pausing this run
 	var/ticks = 1			//how many ticks does this ss take to run on avg.
@@ -46,8 +54,14 @@
 	return
 
 //This is used so the mc knows when the subsystem sleeps. do not override.
-/datum/controller/subsystem/proc/ignite(resumed = 0)
-	set waitfor = 0
+/datum/controller/subsystem/proc/ignite(resumed = FALSE)
+	SHOULD_NOT_OVERRIDE(TRUE)
+	set waitfor = FALSE
+	. = SS_IDLE
+
+	tick_allocation_last = Master.current_ticklimit-(TICK_USAGE)
+	tick_allocation_avg = MC_AVERAGE(tick_allocation_avg, tick_allocation_last)
+
 	. = SS_SLEEPING
 	fire(resumed)
 	. = state