(Performance) Rate limit the rate in which signals are processed for NPC's

common/features.h

@@ -159,6 +159,7 @@ enum {	//timer settings, all in milliseconds
 	AItarget_check_duration = 500,
 	AIClientScanarea_delay = 750,	//used in REVERSE_AGGRO
 	AIassistcheck_delay = 3000,		//now often a fighting NPC will yell for help
+	AI_check_signal_timer_delay = 500, // How often EVENT_SIGNAL checks are processed
 	ClientProximity_interval = 150,
 	CombatEventTimer_expire = 12000,
 	Tribute_duration = 600000,

zone/mob.h

@@ -1262,6 +1262,7 @@ protected:
 	std::unique_ptr<Timer> AIscanarea_timer;
 	std::unique_ptr<Timer> AIwalking_timer;
 	std::unique_ptr<Timer> AIfeignremember_timer;
+	std::unique_ptr<Timer> AI_check_signal_timer;
 	uint32 pLastFightingDelayMoving;
 	HateList hate_list;
 	std::set<uint32> feign_memory_list;

zone/mob_ai.cpp

@@ -429,6 +429,8 @@ void Mob::AI_Init()
 	AItarget_check_timer.reset(nullptr);
 	AIfeignremember_timer.reset(nullptr);
 	AIscanarea_timer.reset(nullptr);
+	AI_check_signal_timer.reset(nullptr);
+
 	minLastFightingDelayMoving = RuleI(NPC, LastFightingDelayMovingMin);
 	maxLastFightingDelayMoving = RuleI(NPC, LastFightingDelayMovingMax);
 
@@ -479,6 +481,8 @@ void Mob::AI_Start(uint32 iMoveDelay) {
 	AItarget_check_timer = std::unique_ptr<Timer>(new Timer(AItarget_check_duration));
 	AIfeignremember_timer = std::unique_ptr<Timer>(new Timer(AIfeignremember_delay));
 	AIscanarea_timer = std::unique_ptr<Timer>(new Timer(AIscanarea_delay));
+	AI_check_signal_timer = std::unique_ptr<Timer>(new Timer(AI_check_signal_timer_delay));
+
 #ifdef REVERSE_AGGRO
 	if(IsNPC() && !CastToNPC()->WillAggroNPCs())
 		AIscanarea_timer->Disable();
@@ -544,6 +548,7 @@ void Mob::AI_Stop() {
 	AItarget_check_timer.reset(nullptr);
 	AIscanarea_timer.reset(nullptr);
 	AIfeignremember_timer.reset(nullptr);
+	AI_check_signal_timer.reset(nullptr);
 
 	hate_list.WipeHateList();
 }
@@ -998,7 +1003,7 @@ void Mob::AI_Process() {
 	}
 
 	// trigger EVENT_SIGNAL if required
-	if(IsNPC()) {
+	if (AI_check_signal_timer->Check() && IsNPC()) {
 		CastToNPC()->CheckSignal();
 	}