diff --git a/source/glest_game/world/world.cpp b/source/glest_game/world/world.cpp
index f59222a2..9c5b46e6 100644
--- a/source/glest_game/world/world.cpp
+++ b/source/glest_game/world/world.cpp
@@ -48,6 +48,8 @@ World::World(){
 	fogOfWarSmoothing= config.getBool("FogOfWarSmoothing");
 	fogOfWarSmoothingFrameSkip= config.getInt("FogOfWarSmoothingFrameSkip");
 
+	bool perfTimerEnabled = SystemFlags::getSystemSettingType(SystemFlags::debugPerformance).enabled;
+
 	frameCount= 0;
 	//nextUnitId= 0;
 
@@ -177,18 +179,19 @@ void World::loadScenario(const string &path, Checksum *checksum){
 // ==================== misc ====================
 
 void World::update(){
-	Chrono chrono;
-	chrono.start();
+	if(perfTimerEnabled == true) {
+		chronoPerfTimer.start();
+	}
 
 	++frameCount;
 
 	//time
 	timeFlow.update();
-	if(chrono.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chrono.getMillis());
+	if(perfTimerEnabled == true && chronoPerfTimer.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chronoPerfTimer.getMillis());
 
 	//water effects
 	waterEffects.update();
-	if(chrono.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chrono.getMillis());
+	if(perfTimerEnabled == true && chronoPerfTimer.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chronoPerfTimer.getMillis());
 
 	//units
 	for(int i=0; i<getFactionCount(); ++i){
@@ -196,7 +199,7 @@ void World::update(){
 			unitUpdater.updateUnit(getFaction(i)->getUnit(j));
 		}
 	}
-	if(chrono.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chrono.getMillis());
+	if(perfTimerEnabled == true && chronoPerfTimer.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chronoPerfTimer.getMillis());
 
 	//undertake the dead
 	for(int i=0; i<getFactionCount(); ++i){
@@ -210,7 +213,7 @@ void World::update(){
 			}
 		}
 	}
-	if(chrono.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chrono.getMillis());
+	if(perfTimerEnabled == true && chronoPerfTimer.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chronoPerfTimer.getMillis());
 
 	//food costs
 	for(int i=0; i<techTree->getResourceTypeCount(); ++i){
@@ -221,21 +224,21 @@ void World::update(){
 			}
 		}
 	}
-	if(chrono.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chrono.getMillis());
+	if(perfTimerEnabled == true && chronoPerfTimer.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chronoPerfTimer.getMillis());
 
 	//fow smoothing
 	if(fogOfWarSmoothing && ((frameCount+1) % (fogOfWarSmoothingFrameSkip+1))==0){
 		float fogFactor= static_cast<float>(frameCount%GameConstants::updateFps)/GameConstants::updateFps;
 		minimap.updateFowTex(clamp(fogFactor, 0.f, 1.f));
 	}
-	if(chrono.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chrono.getMillis());
+	if(perfTimerEnabled == true && chronoPerfTimer.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chronoPerfTimer.getMillis());
 
 	//tick
 	if(frameCount%GameConstants::updateFps==0){
 		computeFow();
 		tick();
 	}
-	if(chrono.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chrono.getMillis());
+	if(perfTimerEnabled == true && chronoPerfTimer.getMillis() > 0) SystemFlags::OutputDebug(SystemFlags::debugPerformance,"In [%s::%s] Line: %d took msecs: %lld\n",__FILE__,__FUNCTION__,__LINE__,chronoPerfTimer.getMillis());
 }
 
 void World::tick(){
@@ -793,10 +796,9 @@ void World::computeFow(){
 					//iterate through all cells
 					PosCircularIterator pci(&map, unit->getPos(), sightRange+indirectSightRange);
 					while(pci.next()){
-						Vec2i pos= pci.getPos();
+						const Vec2i &pos= pci.getPos();
 						Vec2i surfPos= Map::toSurfCoords(pos);
 
-
 						//compute max alpha
 						float maxAlpha;
 						if(surfPos.x>1 && surfPos.y>1 && surfPos.x<map.getSurfaceW()-2 && surfPos.y<map.getSurfaceH()-2){
diff --git a/source/glest_game/world/world.h b/source/glest_game/world/world.h
index ed67b202..8757c43d 100644
--- a/source/glest_game/world/world.h
+++ b/source/glest_game/world/world.h
@@ -91,6 +91,8 @@ private:
 	int fogOfWarSmoothingFrameSkip;
 	bool fogOfWarSmoothing;
 	Game *game;
+	Chrono chronoPerfTimer;
+	bool perfTimerEnabled;
 
 public:
 	World();