From d3d338e64b872094abb50a33ae418de8d13d735b Mon Sep 17 00:00:00 2001
From: JozsefA <jozsefaug@gmail.com>
Date: Fri, 26 Mar 2021 22:02:19 -0700
Subject: [PATCH] STE tick optimization.  - SmartTileEntity#tick down to 3.32%
 from 11.64% cpu time.  - Measured by JFR over 2 sessions each >8min.  - Test
 world was the deployer fields.  - Iterating over HashMap values is slow.  -
 Collect TileEntityBehaviours into a list when the contents of
 SmartTileEntity#behaviours changes.

---
 .../tileEntity/SmartTileEntity.java           | 39 +++++++++++++------
 1 file changed, 27 insertions(+), 12 deletions(-)

diff --git a/src/main/java/com/simibubi/create/foundation/tileEntity/SmartTileEntity.java b/src/main/java/com/simibubi/create/foundation/tileEntity/SmartTileEntity.java
index 9404b3544..37605d859 100644
--- a/src/main/java/com/simibubi/create/foundation/tileEntity/SmartTileEntity.java
+++ b/src/main/java/com/simibubi/create/foundation/tileEntity/SmartTileEntity.java
@@ -17,7 +17,9 @@ import net.minecraftforge.items.CapabilityItemHandler;
 
 public abstract class SmartTileEntity extends SyncedTileEntity implements ITickableTileEntity {
 
-	private Map<BehaviourType<?>, TileEntityBehaviour> behaviours;
+	private final Map<BehaviourType<?>, TileEntityBehaviour> behaviours;
+	// Internally maintained to be identical to behaviorMap.values() in order to improve iteration performance.
+	private final List<TileEntityBehaviour> behaviourList;
 	private boolean initialized;
 	private boolean firstNbtRead;
 	private int lazyTickRate;
@@ -36,6 +38,9 @@ public abstract class SmartTileEntity extends SyncedTileEntity implements ITicka
 		ArrayList<TileEntityBehaviour> list = new ArrayList<>();
 		addBehaviours(list);
 		list.forEach(b -> behaviours.put(b.getType(), b));
+
+		behaviourList = new ArrayList<>(list.size());
+		updateBehaviorList();
 	}
 
 	public abstract void addBehaviours(List<TileEntityBehaviour> behaviours);
@@ -58,13 +63,11 @@ public abstract class SmartTileEntity extends SyncedTileEntity implements ITicka
 			lazyTick();
 		}
 
-		behaviours.values()
-			.forEach(TileEntityBehaviour::tick);
+		behaviourList.forEach(TileEntityBehaviour::tick);
 	}
 
 	public void initialize() {
-		behaviours.values()
-			.forEach(TileEntityBehaviour::initialize);
+		behaviourList.forEach(TileEntityBehaviour::initialize);
 		lazyTick();
 	}
 
@@ -99,10 +102,11 @@ public abstract class SmartTileEntity extends SyncedTileEntity implements ITicka
 			ArrayList<TileEntityBehaviour> list = new ArrayList<>();
 			addBehavioursDeferred(list);
 			list.forEach(b -> behaviours.put(b.getType(), b));
+
+			updateBehaviorList();
 		}
 		super.read(compound);
-		behaviours.values()
-			.forEach(tb -> tb.read(compound, clientPacket));
+		behaviourList.forEach(tb -> tb.read(compound, clientPacket));
 	}
 
 	/**
@@ -110,8 +114,7 @@ public abstract class SmartTileEntity extends SyncedTileEntity implements ITicka
 	 */
 	protected void write(CompoundNBT compound, boolean clientPacket) {
 		super.write(compound);
-		behaviours.values()
-			.forEach(tb -> tb.write(compound, clientPacket));
+		behaviourList.forEach(tb -> tb.write(compound, clientPacket));
 	}
 
 	@Override
@@ -130,19 +133,31 @@ public abstract class SmartTileEntity extends SyncedTileEntity implements ITicka
 	}
 
 	protected void forEachBehaviour(Consumer<TileEntityBehaviour> action) {
-		behaviours.values()
-			.forEach(action);
+		behaviourList.forEach(action);
 	}
 
 	protected void attachBehaviourLate(TileEntityBehaviour behaviour) {
 		behaviours.put(behaviour.getType(), behaviour);
 		behaviour.initialize();
+
+		updateBehaviorList();
 	}
 
 	protected void removeBehaviour(BehaviourType<?> type) {
 		TileEntityBehaviour remove = behaviours.remove(type);
-		if (remove != null)
+		if (remove != null) {
 			remove.remove();
+			updateBehaviorList();
+		}
+	}
+
+	// We don't trust the input to the API will be sane, so we
+	// update all the contents whenever something changes. It's
+	// simpler than trying to manipulate the list one element at
+	// a time.
+	private void updateBehaviorList() {
+		behaviourList.clear();
+		behaviourList.addAll(behaviours.values());
 	}
 
 	@SuppressWarnings("unchecked")