Rewrite chunk system (#8177)

Patch documentation to come

Issues with the old system that are fixed now:
- World generation does not scale with cpu cores effectively.
- Relies on the main thread for scheduling and maintaining chunk state, dropping chunk load/generate rates at lower tps.
- Unreliable prioritisation of chunk gen/load calls that block the main thread.
- Shutdown logic is utterly unreliable, as it has to wait for all chunks to unload - is it guaranteed that the chunk system is in a state on shutdown that it can reliably do this? Watchdog shutdown also typically failed due to thread checks, which is now resolved.
- Saving of data is not unified (i.e can save chunk data without saving entity data, poses problems for desync if shutdown is really abnormal.
- Entities are not loaded with chunks. This caused quite a bit of headache for Chunk#getEntities API, but now the new chunk system loads entities with chunks so that they are ready whenever the chunk loads in. Effectively brings the behavior back to 1.16 era, but still storing entities in their own separate regionfiles.

The above list is not complete. The patch documentation will complete it.

New chunk system hard relies on starlight and dataconverter, and most importantly the new concurrent utilities in ConcurrentUtil.

Some of the old async chunk i/o interface (i.e the old file io thread reroutes _some_ calls to the new file io thread) is kept for plugin compat reasons. It will be removed in the next major version of minecraft.

The old legacy chunk system patches have been moved to the removed folder in case we need them again.

1 files changed, 808 insertions, 0 deletions

diff --git a/patches/server/0346-Entity-Activation-Range-2.0.patch b/patches/server/0346-Entity-Activation-Range-2.0.patch
new file mode 100644
index 0000000000..c223b23f30
--- /dev/null
+++ b/patches/server/0346-Entity-Activation-Range-2.0.patch
@@ -0,0 +1,808 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Aikar <[email protected]>
+Date: Fri, 13 May 2016 01:38:06 -0400
+Subject: [PATCH] Entity Activation Range 2.0
+
+Optimizes performance of Activation Range
+
+Adds many new configurations and a new wake up inactive system
+
+Fixes and adds new Immunities to improve gameplay behavior
+
+Adds water Mobs to activation range config and nerfs fish
+Adds flying monsters to control ghast and phantoms
+Adds villagers as separate config
+
+diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
+index cdb04f32d61590a2a23903de26bab0a4b334569d..28922059f1a58ae98282ab59b0a9e9014127b12a 100644
+--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
++++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
+@@ -2,7 +2,6 @@ package net.minecraft.server.level;
+ 
+ import com.google.common.annotations.VisibleForTesting;
+ import co.aikar.timings.TimingHistory; // Paper
+-import co.aikar.timings.Timings; // Paper
+ import com.google.common.collect.Lists;
+ import com.mojang.datafixers.DataFixer;
+ import com.mojang.datafixers.util.Pair;
+@@ -1026,17 +1025,17 @@ public class ServerLevel extends Level implements WorldGenLevel {
+         ++TimingHistory.entityTicks; // Paper - timings
+         // Spigot start
+         co.aikar.timings.Timing timer; // Paper
+-        if (!org.spigotmc.ActivationRange.checkIfActive(entity)) {
++        /*if (!org.spigotmc.ActivationRange.checkIfActive(entity)) { // Paper - comment out - EAR 2, reimplement below
+             entity.tickCount++;
+             timer = entity.getType().inactiveTickTimer.startTiming(); try { // Paper - timings
+             entity.inactiveTick();
+             } finally { timer.stopTiming(); } // Paper
+             return;
+-        }
++        }*/ // Paper - comment out EAR 2
+         // Spigot end
+         // Paper start- timings
+-        TimingHistory.activatedEntityTicks++;
+-        timer = entity.getVehicle() != null ? entity.getType().passengerTickTimer.startTiming() : entity.getType().tickTimer.startTiming();
++        final boolean isActive = org.spigotmc.ActivationRange.checkIfActive(entity);
++        timer = isActive ? entity.getType().tickTimer.startTiming() : entity.getType().inactiveTickTimer.startTiming(); // Paper
+         try {
+         // Paper end - timings
+         entity.setOldPosAndRot();
+@@ -1047,9 +1046,13 @@ public class ServerLevel extends Level implements WorldGenLevel {
+             return Registry.ENTITY_TYPE.getKey(entity.getType()).toString();
+         });
+         gameprofilerfiller.incrementCounter("tickNonPassenger");
++        if (isActive) { // Paper - EAR 2
++            TimingHistory.activatedEntityTicks++;
+         entity.tick();
+         entity.postTick(); // CraftBukkit
++        } else { entity.inactiveTick(); } // Paper - EAR 2
+         this.getProfiler().pop();
++        } finally { timer.stopTiming(); } // Paper - timings
+         Iterator iterator = entity.getPassengers().iterator();
+ 
+         while (iterator.hasNext()) {
+@@ -1057,13 +1060,18 @@ public class ServerLevel extends Level implements WorldGenLevel {
+ 
+             this.tickPassenger(entity, entity1);
+         }
+-        } finally { timer.stopTiming(); } // Paper - timings
++        // } finally { timer.stopTiming(); } // Paper - timings - move up
+ 
+     }
+ 
+     private void tickPassenger(Entity vehicle, Entity passenger) {
+         if (!passenger.isRemoved() && passenger.getVehicle() == vehicle) {
+             if (passenger instanceof Player || this.entityTickList.contains(passenger)) {
++                // Paper - EAR 2
++                final boolean isActive = org.spigotmc.ActivationRange.checkIfActive(passenger);
++                co.aikar.timings.Timing timer = isActive ? passenger.getType().passengerTickTimer.startTiming() : passenger.getType().passengerInactiveTickTimer.startTiming(); // Paper
++                try {
++                // Paper end
+                 passenger.setOldPosAndRot();
+                 ++passenger.tickCount;
+                 ProfilerFiller gameprofilerfiller = this.getProfiler();
+@@ -1072,8 +1080,17 @@ public class ServerLevel extends Level implements WorldGenLevel {
+                     return Registry.ENTITY_TYPE.getKey(passenger.getType()).toString();
+                 });
+                 gameprofilerfiller.incrementCounter("tickPassenger");
++                // Paper start - EAR 2
++                if (isActive) {
+                 passenger.rideTick();
+                 passenger.postTick(); // CraftBukkit
++                } else {
++                    passenger.setDeltaMovement(Vec3.ZERO);
++                    passenger.inactiveTick();
++                    // copied from inside of if (isPassenger()) of passengerTick, but that ifPassenger is unnecessary
++                    vehicle.positionRider(passenger);
++                }
++                // Paper end - EAR 2
+                 gameprofilerfiller.pop();
+                 Iterator iterator = passenger.getPassengers().iterator();
+ 
+@@ -1083,6 +1100,7 @@ public class ServerLevel extends Level implements WorldGenLevel {
+                     this.tickPassenger(passenger, entity2);
+                 }
+ 
++            } finally { timer.stopTiming(); }// Paper - EAR2 timings
+             }
+         } else {
+             passenger.stopRiding();
+diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
+index fa128e7f8089339f932e19edf95a8d5c0cc14046..c5b1d2e4b577a3f4ad352dc6a8436c04411efa8b 100644
+--- a/src/main/java/net/minecraft/world/entity/Entity.java
++++ b/src/main/java/net/minecraft/world/entity/Entity.java
+@@ -384,6 +384,8 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource {
+     public void inactiveTick() { }
+     // Spigot end
+     // Paper start
++    public long activatedImmunityTick = Integer.MIN_VALUE; // Paper
++    public boolean isTemporarilyActive = false; // Paper
+     protected int numCollisions = 0; // Paper
+     public boolean spawnedViaMobSpawner; // Paper - Yes this name is similar to above, upstream took the better one
+     @javax.annotation.Nullable
+@@ -909,6 +911,8 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource {
+         } else {
+             this.wasOnFire = this.isOnFire();
+             if (movementType == MoverType.PISTON) {
++                this.activatedTick = Math.max(this.activatedTick, MinecraftServer.currentTick + 20); // Paper
++                this.activatedImmunityTick = Math.max(this.activatedImmunityTick, MinecraftServer.currentTick + 20);   // Paper
+                 movement = this.limitPistonMovement(movement);
+                 if (movement.equals(Vec3.ZERO)) {
+                     return;
+@@ -921,6 +925,13 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource {
+                 this.stuckSpeedMultiplier = Vec3.ZERO;
+                 this.setDeltaMovement(Vec3.ZERO);
+             }
++            // Paper start - ignore movement changes while inactive.
++            if (isTemporarilyActive && !(this instanceof ItemEntity || this instanceof net.minecraft.world.entity.vehicle.AbstractMinecart) && movement == getDeltaMovement() && movementType == MoverType.SELF) {
++                setDeltaMovement(Vec3.ZERO);
++                this.level.getProfiler().pop();
++                return;
++            }
++            // Paper end
+ 
+             movement = this.maybeBackOffFromEdge(movement, movementType);
+             Vec3 vec3d1 = this.collide(movement);
+diff --git a/src/main/java/net/minecraft/world/entity/Mob.java b/src/main/java/net/minecraft/world/entity/Mob.java
+index 37102e8cdaeb558e80889ff553656f14eaaeb650..d7b137a84deea68c75ee0b3c99b089b8dff25947 100644
+--- a/src/main/java/net/minecraft/world/entity/Mob.java
++++ b/src/main/java/net/minecraft/world/entity/Mob.java
+@@ -210,6 +210,19 @@ public abstract class Mob extends LivingEntity {
+         return this.lookControl;
+     }
+ 
++    // Paper start
++    @Override
++    public void inactiveTick() {
++        super.inactiveTick();
++        if (this.goalSelector.inactiveTick()) {
++            this.goalSelector.tick();
++        }
++        if (this.targetSelector.inactiveTick()) {
++            this.targetSelector.tick();
++        }
++    }
++    // Paper end
++
+     public MoveControl getMoveControl() {
+         if (this.isPassenger() && this.getVehicle() instanceof Mob) {
+             Mob entityinsentient = (Mob) this.getVehicle();
+diff --git a/src/main/java/net/minecraft/world/entity/PathfinderMob.java b/src/main/java/net/minecraft/world/entity/PathfinderMob.java
+index 2df5b50be11297941d13ec9d17001f488af11750..3db309e709cd72e3aae184ff2f8b1a7b98f2c7a8 100644
+--- a/src/main/java/net/minecraft/world/entity/PathfinderMob.java
++++ b/src/main/java/net/minecraft/world/entity/PathfinderMob.java
+@@ -19,6 +19,7 @@ public abstract class PathfinderMob extends Mob {
+     }
+ 
+     public org.bukkit.craftbukkit.entity.CraftCreature getBukkitCreature() { return (org.bukkit.craftbukkit.entity.CraftCreature) super.getBukkitEntity(); } // Paper
++    public BlockPos movingTarget = null; public BlockPos getMovingTarget() { return movingTarget; } // Paper
+ 
+     public float getWalkTargetValue(BlockPos pos) {
+         return this.getWalkTargetValue(pos, this.level);
+diff --git a/src/main/java/net/minecraft/world/entity/ai/goal/GoalSelector.java b/src/main/java/net/minecraft/world/entity/ai/goal/GoalSelector.java
+index 3e981fbf81f21b40652f7a05d4a7a37065db4b00..19ee04dd92b39a775260f832ca8880335d24988b 100644
+--- a/src/main/java/net/minecraft/world/entity/ai/goal/GoalSelector.java
++++ b/src/main/java/net/minecraft/world/entity/ai/goal/GoalSelector.java
+@@ -32,6 +32,7 @@ public class GoalSelector {
+     private final EnumSet<Goal.Flag> disabledFlags = EnumSet.noneOf(Goal.Flag.class);
+     private int tickCount;
+     private int newGoalRate = 3;
++    private int curRate;
+ 
+     public GoalSelector(Supplier<ProfilerFiller> profiler) {
+         this.profiler = profiler;
+@@ -46,6 +47,20 @@ public class GoalSelector {
+         this.availableGoals.clear();
+     }
+ 
++    // Paper start
++    public boolean inactiveTick() {
++        this.curRate++;
++        return this.curRate % this.newGoalRate == 0;
++    }
++    public boolean hasTasks() {
++        for (WrappedGoal task : this.availableGoals) {
++            if (task.isRunning()) {
++                return true;
++            }
++        }
++        return false;
++    }
++    // Paper end
+     public void removeGoal(Goal goal) {
+         this.availableGoals.stream().filter((wrappedGoal) -> {
+             return wrappedGoal.getGoal() == goal;
+diff --git a/src/main/java/net/minecraft/world/entity/ai/goal/MoveToBlockGoal.java b/src/main/java/net/minecraft/world/entity/ai/goal/MoveToBlockGoal.java
+index 6efba52c2e5d7811ee329ed22c1c76f75d7ddbe1..26bf383caea68834c654b25653ced9017f1b1b22 100644
+--- a/src/main/java/net/minecraft/world/entity/ai/goal/MoveToBlockGoal.java
++++ b/src/main/java/net/minecraft/world/entity/ai/goal/MoveToBlockGoal.java
+@@ -14,7 +14,7 @@ public abstract class MoveToBlockGoal extends Goal {
+     protected int nextStartTick;
+     protected int tryTicks;
+     private int maxStayTicks;
+-    protected BlockPos blockPos = BlockPos.ZERO; @Deprecated public final BlockPos getTargetPosition() { return this.blockPos; } // Paper - OBFHELPER
++    protected BlockPos blockPos = BlockPos.ZERO; @Deprecated public final BlockPos getTargetPosition() { return this.blockPos; } @Deprecated public void setTargetPosition(BlockPos pos) { this.blockPos = pos; mob.movingTarget = pos != BlockPos.ZERO ? pos : null; } // Paper - OBFHELPER
+     private boolean reachedTarget;
+     private final int searchRange;
+     private final int verticalSearchRange;
+@@ -23,6 +23,13 @@ public abstract class MoveToBlockGoal extends Goal {
+     public MoveToBlockGoal(PathfinderMob mob, double speed, int range) {
+         this(mob, speed, range, 1);
+     }
++    // Paper start - activation range improvements
++    @Override
++    public void stop() {
++        super.stop();
++        setTargetPosition(BlockPos.ZERO);
++    }
++    // Paper end
+ 
+     public MoveToBlockGoal(PathfinderMob mob, double speed, int range, int maxYDifference) {
+         this.mob = mob;
+@@ -114,6 +121,7 @@ public abstract class MoveToBlockGoal extends Goal {
+                         mutableBlockPos.setWithOffset(blockPos, m, k - 1, n);
+                         if (this.mob.isWithinRestriction(mutableBlockPos) && this.isValidTarget(this.mob.level, mutableBlockPos)) {
+                             this.blockPos = mutableBlockPos;
++                            setTargetPosition(mutableBlockPos.immutable()); // Paper
+                             return true;
+                         }
+                     }
+diff --git a/src/main/java/net/minecraft/world/entity/npc/Villager.java b/src/main/java/net/minecraft/world/entity/npc/Villager.java
+index f957c0aca36b7228ac3a33ca04c948b1d10642d1..39fc94b1e1555fd6706391223dd2783139b16016 100644
+--- a/src/main/java/net/minecraft/world/entity/npc/Villager.java
++++ b/src/main/java/net/minecraft/world/entity/npc/Villager.java
+@@ -225,17 +225,29 @@ public class Villager extends AbstractVillager implements ReputationEventHandler
+     @Override
+     public void inactiveTick() {
+         // SPIGOT-3874, SPIGOT-3894, SPIGOT-3846, SPIGOT-5286 :(
+-        if (level.spigotConfig.tickInactiveVillagers && this.isEffectiveAi()) {
+-            this.customServerAiStep();
++        // Paper start
++        if (this.getUnhappyCounter() > 0) {
++            this.setUnhappyCounter(this.getUnhappyCounter() - 1);
++        }
++        if (this.isEffectiveAi()) {
++            if (level.spigotConfig.tickInactiveVillagers) {
++                this.customServerAiStep();
++            } else {
++                this.mobTick(true);
++            }
+         }
++        maybeDecayGossip();
++        // Paper end
++
+         super.inactiveTick();
+     }
+     // Spigot End
+ 
+     @Override
+-    protected void customServerAiStep() {
++    protected void customServerAiStep() { mobTick(false); }
++    protected void mobTick(boolean inactive) {
+         this.level.getProfiler().push("villagerBrain");
+-        this.getBrain().tick((ServerLevel) this.level, this);
++        if (!inactive) this.getBrain().tick((ServerLevel) this.level, this); // Paper
+         this.level.getProfiler().pop();
+         if (this.assignProfessionWhenSpawned) {
+             this.assignProfessionWhenSpawned = false;
+@@ -259,7 +271,7 @@ public class Villager extends AbstractVillager implements ReputationEventHandler
+             this.lastTradedPlayer = null;
+         }
+ 
+-        if (!this.isNoAi() && this.random.nextInt(100) == 0) {
++        if (!inactive && !this.isNoAi() && this.random.nextInt(100) == 0) { // Paper
+             Raid raid = ((ServerLevel) this.level).getRaidAt(this.blockPosition());
+ 
+             if (raid != null && raid.isActive() && !raid.isOver()) {
+@@ -270,6 +282,7 @@ public class Villager extends AbstractVillager implements ReputationEventHandler
+         if (this.getVillagerData().getProfession() == VillagerProfession.NONE && this.isTrading()) {
+             this.stopTrading();
+         }
++        if (inactive) return; // Paper
+ 
+         super.customServerAiStep();
+     }
+diff --git a/src/main/java/net/minecraft/world/entity/vehicle/MinecartHopper.java b/src/main/java/net/minecraft/world/entity/vehicle/MinecartHopper.java
+index 540c23f6297c34cf8e7bf8312ceaa5fc868f414c..2866385a64b22b7dc82b6122c62bcea6b0908a60 100644
+--- a/src/main/java/net/minecraft/world/entity/vehicle/MinecartHopper.java
++++ b/src/main/java/net/minecraft/world/entity/vehicle/MinecartHopper.java
+@@ -57,6 +57,7 @@ public class MinecartHopper extends AbstractMinecartContainer implements Hopper
+         if (bl != this.isEnabled()) {
+             this.setEnabled(bl);
+         }
++        this.immunize();  // Paper
+ 
+     }
+ 
+@@ -107,11 +108,13 @@ public class MinecartHopper extends AbstractMinecartContainer implements Hopper
+ 
+     public boolean suckInItems() {
+         if (HopperBlockEntity.suckInItems(this.level, this)) {
++            this.immunize();  // Paper
+             return true;
+         } else {
+             List<ItemEntity> list = this.level.getEntitiesOfClass(ItemEntity.class, this.getBoundingBox().inflate(0.25D, 0.0D, 0.25D), EntitySelector.ENTITY_STILL_ALIVE);
+             if (!list.isEmpty()) {
+                 HopperBlockEntity.addItem(this, list.get(0));
++                this.immunize();  // Paper
+             }
+ 
+             return false;
+@@ -149,4 +152,11 @@ public class MinecartHopper extends AbstractMinecartContainer implements Hopper
+     public AbstractContainerMenu createMenu(int syncId, Inventory playerInventory) {
+         return new HopperMenu(syncId, playerInventory, this);
+     }
++
++    // Paper start
++    public void immunize() {
++        this.activatedImmunityTick = Math.max(this.activatedImmunityTick, net.minecraft.server.MinecraftServer.currentTick + 20);
++    }
++    // Paper end
++
+ }
+diff --git a/src/main/java/net/minecraft/world/level/Level.java b/src/main/java/net/minecraft/world/level/Level.java
+index cb7e92f2694cefeecebc840959a01e1e1945061a..10a5315c6a2f872d88c080910eeca140ac6fbbc4 100644
+--- a/src/main/java/net/minecraft/world/level/Level.java
++++ b/src/main/java/net/minecraft/world/level/Level.java
+@@ -158,6 +158,12 @@ public abstract class Level implements LevelAccessor, AutoCloseable {
+     public Map<BlockPos, BlockEntity> capturedTileEntities = new HashMap<>();
+     public List<ItemEntity> captureDrops;
+     public final it.unimi.dsi.fastutil.objects.Object2LongOpenHashMap<SpawnCategory> ticksPerSpawnCategory = new it.unimi.dsi.fastutil.objects.Object2LongOpenHashMap<>();
++    // Paper start
++    public int wakeupInactiveRemainingAnimals;
++    public int wakeupInactiveRemainingFlying;
++    public int wakeupInactiveRemainingMonsters;
++    public int wakeupInactiveRemainingVillagers;
++    // Paper end
+     public boolean populating;
+     public final org.spigotmc.SpigotWorldConfig spigotConfig; // Spigot
+     // Paper start
+diff --git a/src/main/java/net/minecraft/world/level/block/piston/PistonMovingBlockEntity.java b/src/main/java/net/minecraft/world/level/block/piston/PistonMovingBlockEntity.java
+index 4b55b667eebfe50dfeda89015112e275e71b9777..dda0b32a4989bbead35a2219a969a30ba0e975b0 100644
+--- a/src/main/java/net/minecraft/world/level/block/piston/PistonMovingBlockEntity.java
++++ b/src/main/java/net/minecraft/world/level/block/piston/PistonMovingBlockEntity.java
+@@ -140,6 +140,10 @@ public class PistonMovingBlockEntity extends BlockEntity {
+                                 }
+ 
+                                 entity.setDeltaMovement(e, g, h);
++                                // Paper - EAR items stuck in in slime pushed by a piston
++                                entity.activatedTick = Math.max(entity.activatedTick, net.minecraft.server.MinecraftServer.currentTick + 10);
++                                entity.activatedImmunityTick = Math.max(entity.activatedImmunityTick, net.minecraft.server.MinecraftServer.currentTick + 10);
++                                // Paper end
+                                 break;
+                             }
+                         }
+diff --git a/src/main/java/org/spigotmc/ActivationRange.java b/src/main/java/org/spigotmc/ActivationRange.java
+index 2861c585710eaa00541ff417a29f1f6a2fb5b46a..b1ed97618d08d7691d24f89e9e9b0ed0f2bddd09 100644
+--- a/src/main/java/org/spigotmc/ActivationRange.java
++++ b/src/main/java/org/spigotmc/ActivationRange.java
+@@ -1,39 +1,52 @@
+ package org.spigotmc;
+ 
++import net.minecraft.core.BlockPos;
+ import net.minecraft.server.MinecraftServer;
++import net.minecraft.server.level.ServerChunkCache;
+ import net.minecraft.world.entity.Entity;
+ import net.minecraft.world.entity.ExperienceOrb;
++import net.minecraft.world.entity.FlyingMob;
+ import net.minecraft.world.entity.LightningBolt;
+ import net.minecraft.world.entity.LivingEntity;
++import net.minecraft.world.entity.Mob;
+ import net.minecraft.world.entity.PathfinderMob;
++import net.minecraft.world.entity.ai.Brain;
+ import net.minecraft.world.entity.ambient.AmbientCreature;
+ import net.minecraft.world.entity.animal.Animal;
++import net.minecraft.world.entity.animal.Bee;
+ import net.minecraft.world.entity.animal.Sheep;
++import net.minecraft.world.entity.animal.WaterAnimal;
++import net.minecraft.world.entity.animal.horse.Llama;
+ import net.minecraft.world.entity.boss.EnderDragonPart;
+ import net.minecraft.world.entity.boss.enderdragon.EndCrystal;
+ import net.minecraft.world.entity.boss.enderdragon.EnderDragon;
+ import net.minecraft.world.entity.boss.wither.WitherBoss;
+ import net.minecraft.world.entity.item.PrimedTnt;
+ import net.minecraft.world.entity.monster.Creeper;
+-import net.minecraft.world.entity.monster.Monster;
+-import net.minecraft.world.entity.monster.Slime;
++import net.minecraft.world.entity.monster.Enemy;
++import net.minecraft.world.entity.monster.Pillager;
+ import net.minecraft.world.entity.npc.Villager;
+ import net.minecraft.world.entity.player.Player;
+ import net.minecraft.world.entity.projectile.AbstractArrow;
+ import net.minecraft.world.entity.projectile.AbstractHurtingProjectile;
++import net.minecraft.world.entity.projectile.EyeOfEnder;
+ import net.minecraft.world.entity.projectile.FireworkRocketEntity;
+ import net.minecraft.world.entity.projectile.ThrowableProjectile;
+ import net.minecraft.world.entity.projectile.ThrownTrident;
+ import net.minecraft.world.entity.raid.Raider;
++import co.aikar.timings.MinecraftTimings;
++import net.minecraft.world.entity.schedule.Activity;
+ import net.minecraft.world.level.Level;
+ import net.minecraft.world.phys.AABB;
+-import co.aikar.timings.MinecraftTimings;
+ 
+ public class ActivationRange
+ {
+ 
+     public enum ActivationType
+     {
++        WATER, // Paper
++        FLYING_MONSTER, // Paper
++        VILLAGER, // Paper
+         MONSTER,
+         ANIMAL,
+         RAIDER,
+@@ -41,6 +54,43 @@ public class ActivationRange
+ 
+         AABB boundingBox = new AABB( 0, 0, 0, 0, 0, 0 );
+     }
++    // Paper start
++
++    static Activity[] VILLAGER_PANIC_IMMUNITIES = {
++        Activity.HIDE,
++        Activity.PRE_RAID,
++        Activity.RAID,
++        Activity.PANIC
++    };
++
++    private static int checkInactiveWakeup(Entity entity) {
++        Level world = entity.level;
++        SpigotWorldConfig config = world.spigotConfig;
++        long inactiveFor = MinecraftServer.currentTick - entity.activatedTick;
++        if (entity.activationType == ActivationType.VILLAGER) {
++            if (inactiveFor > config.wakeUpInactiveVillagersEvery && world.wakeupInactiveRemainingVillagers > 0) {
++                world.wakeupInactiveRemainingVillagers--;
++                return config.wakeUpInactiveVillagersFor;
++            }
++        } else if (entity.activationType == ActivationType.ANIMAL) {
++            if (inactiveFor > config.wakeUpInactiveAnimalsEvery && world.wakeupInactiveRemainingAnimals > 0) {
++                world.wakeupInactiveRemainingAnimals--;
++                return config.wakeUpInactiveAnimalsFor;
++            }
++        } else if (entity.activationType == ActivationType.FLYING_MONSTER) {
++            if (inactiveFor > config.wakeUpInactiveFlyingEvery && world.wakeupInactiveRemainingFlying > 0) {
++                world.wakeupInactiveRemainingFlying--;
++                return config.wakeUpInactiveFlyingFor;
++            }
++        } else if (entity.activationType == ActivationType.MONSTER || entity.activationType == ActivationType.RAIDER) {
++            if (inactiveFor > config.wakeUpInactiveMonstersEvery && world.wakeupInactiveRemainingMonsters > 0) {
++                world.wakeupInactiveRemainingMonsters--;
++                return config.wakeUpInactiveMonstersFor;
++            }
++        }
++        return -1;
++    }
++    // Paper end
+ 
+     static AABB maxBB = new AABB( 0, 0, 0, 0, 0, 0 );
+ 
+@@ -53,10 +103,13 @@ public class ActivationRange
+      */
+     public static ActivationType initializeEntityActivationType(Entity entity)
+     {
++        if (entity instanceof WaterAnimal) { return ActivationType.WATER; } // Paper
++        else if (entity instanceof Villager) { return ActivationType.VILLAGER; } // Paper
++        else if (entity instanceof FlyingMob && entity instanceof Enemy) { return ActivationType.FLYING_MONSTER; } // Paper - doing & Monster incase Flying no longer includes monster in future
+         if ( entity instanceof Raider )
+         {
+             return ActivationType.RAIDER;
+-        } else if ( entity instanceof Monster || entity instanceof Slime )
++        } else if ( entity instanceof Enemy ) // Paper - correct monster check
+         {
+             return ActivationType.MONSTER;
+         } else if ( entity instanceof PathfinderMob || entity instanceof AmbientCreature )
+@@ -77,10 +130,14 @@ public class ActivationRange
+      */
+     public static boolean initializeEntityActivationState(Entity entity, SpigotWorldConfig config)
+     {
+-        if ( ( entity.activationType == ActivationType.MISC && config.miscActivationRange == 0 )
+-                || ( entity.activationType == ActivationType.RAIDER && config.raiderActivationRange == 0 )
+-                || ( entity.activationType == ActivationType.ANIMAL && config.animalActivationRange == 0 )
+-                || ( entity.activationType == ActivationType.MONSTER && config.monsterActivationRange == 0 )
++        if ( ( entity.activationType == ActivationType.MISC && config.miscActivationRange <= 0 )
++                || ( entity.activationType == ActivationType.RAIDER && config.raiderActivationRange <= 0 )
++                || ( entity.activationType == ActivationType.ANIMAL && config.animalActivationRange <= 0 )
++                || ( entity.activationType == ActivationType.MONSTER && config.monsterActivationRange <= 0 )
++                || ( entity.activationType == ActivationType.VILLAGER && config.villagerActivationRange <= 0 ) // Paper
++                || ( entity.activationType == ActivationType.WATER && config.waterActivationRange <= 0 ) // Paper
++                || ( entity.activationType == ActivationType.FLYING_MONSTER && config.flyingMonsterActivationRange <= 0 ) // Paper
++                || entity instanceof EyeOfEnder // Paper
+                 || entity instanceof Player
+                 || entity instanceof ThrowableProjectile
+                 || entity instanceof EnderDragon
+@@ -113,10 +170,25 @@ public class ActivationRange
+         final int raiderActivationRange = world.spigotConfig.raiderActivationRange;
+         final int animalActivationRange = world.spigotConfig.animalActivationRange;
+         final int monsterActivationRange = world.spigotConfig.monsterActivationRange;
++        // Paper start
++        final int waterActivationRange = world.spigotConfig.waterActivationRange;
++        final int flyingActivationRange = world.spigotConfig.flyingMonsterActivationRange;
++        final int villagerActivationRange = world.spigotConfig.villagerActivationRange;
++        world.wakeupInactiveRemainingAnimals = Math.min(world.wakeupInactiveRemainingAnimals + 1, world.spigotConfig.wakeUpInactiveAnimals);
++        world.wakeupInactiveRemainingVillagers = Math.min(world.wakeupInactiveRemainingVillagers + 1, world.spigotConfig.wakeUpInactiveVillagers);
++        world.wakeupInactiveRemainingMonsters = Math.min(world.wakeupInactiveRemainingMonsters + 1, world.spigotConfig.wakeUpInactiveMonsters);
++        world.wakeupInactiveRemainingFlying = Math.min(world.wakeupInactiveRemainingFlying + 1, world.spigotConfig.wakeUpInactiveFlying);
++        final ServerChunkCache chunkProvider = (ServerChunkCache) world.getChunkSource();
++        // Paper end
+ 
+         int maxRange = Math.max( monsterActivationRange, animalActivationRange );
+         maxRange = Math.max( maxRange, raiderActivationRange );
+         maxRange = Math.max( maxRange, miscActivationRange );
++        // Paper start
++        maxRange = Math.max( maxRange, flyingActivationRange );
++        maxRange = Math.max( maxRange, waterActivationRange );
++        maxRange = Math.max( maxRange, villagerActivationRange );
++        // Paper end
+         maxRange = Math.min( ( world.spigotConfig.simulationDistance << 4 ) - 8, maxRange );
+ 
+         for ( Player player : world.players() )
+@@ -127,11 +199,17 @@ public class ActivationRange
+                 continue;
+             }
+ 
+-            ActivationRange.maxBB = player.getBoundingBox().inflate( maxRange, 256, maxRange );
+-            ActivationType.MISC.boundingBox = player.getBoundingBox().inflate( miscActivationRange, 256, miscActivationRange );
+-            ActivationType.RAIDER.boundingBox = player.getBoundingBox().inflate( raiderActivationRange, 256, raiderActivationRange );
+-            ActivationType.ANIMAL.boundingBox = player.getBoundingBox().inflate( animalActivationRange, 256, animalActivationRange );
+-            ActivationType.MONSTER.boundingBox = player.getBoundingBox().inflate( monsterActivationRange, 256, monsterActivationRange );
++            // Paper start
++            int worldHeight = world.getHeight();
++            ActivationRange.maxBB = player.getBoundingBox().inflate( maxRange, worldHeight, maxRange );
++            ActivationType.MISC.boundingBox = player.getBoundingBox().inflate( miscActivationRange, worldHeight, miscActivationRange );
++            ActivationType.RAIDER.boundingBox = player.getBoundingBox().inflate( raiderActivationRange, worldHeight, raiderActivationRange );
++            ActivationType.ANIMAL.boundingBox = player.getBoundingBox().inflate( animalActivationRange, worldHeight, animalActivationRange );
++            ActivationType.MONSTER.boundingBox = player.getBoundingBox().inflate( monsterActivationRange, worldHeight, monsterActivationRange );
++            ActivationType.WATER.boundingBox = player.getBoundingBox().inflate( waterActivationRange, worldHeight, waterActivationRange );
++            ActivationType.FLYING_MONSTER.boundingBox = player.getBoundingBox().inflate( flyingActivationRange, worldHeight, flyingActivationRange );
++            ActivationType.VILLAGER.boundingBox = player.getBoundingBox().inflate( villagerActivationRange, worldHeight, villagerActivationRange );
++            // Paper end
+ 
+             // Paper start
+             java.util.List<Entity> entities = world.getEntities((Entity)null, maxBB, null);
+@@ -172,60 +250,118 @@ public class ActivationRange
+      * @param entity
+      * @return
+      */
+-    public static boolean checkEntityImmunities(Entity entity)
++    public static int checkEntityImmunities(Entity entity) // Paper - return # of ticks to get immunity
+     {
++        // Paper start
++        SpigotWorldConfig config = entity.level.spigotConfig;
++        int inactiveWakeUpImmunity = checkInactiveWakeup(entity);
++        if (inactiveWakeUpImmunity > -1) {
++            return inactiveWakeUpImmunity;
++        }
++        if (entity.remainingFireTicks > 0) {
++            return 2;
++        }
++        if (entity.activatedImmunityTick >= MinecraftServer.currentTick) {
++            return 1;
++        }
++        long inactiveFor = MinecraftServer.currentTick - entity.activatedTick;
++        // Paper end
+         // quick checks.
+-        if ( entity.wasTouchingWater || entity.remainingFireTicks > 0 )
++        if ( (entity.activationType != ActivationType.WATER && entity.wasTouchingWater && entity.isPushedByFluid()) ) // Paper
+         {
+-            return true;
++            return 100; // Paper
++        }
++        // Paper start
++        if ( !entity.isOnGround() || entity.getDeltaMovement().horizontalDistanceSqr() > 9.999999747378752E-6D )
++        {
++            return 100;
+         }
++        // Paper end
+         if ( !( entity instanceof AbstractArrow ) )
+         {
+-            if ( !entity.isOnGround() || !entity.passengers.isEmpty() || entity.isPassenger() )
++            if ( (!entity.isOnGround() && !(entity instanceof FlyingMob)) ) // Paper - remove passengers logic
+             {
+-                return true;
++                return 10; // Paper
+             }
+         } else if ( !( (AbstractArrow) entity ).inGround )
+         {
+-            return true;
++            return 1; // Paper
+         }
+         // special cases.
+         if ( entity instanceof LivingEntity )
+         {
+             LivingEntity living = (LivingEntity) entity;
+-            if ( /*TODO: Missed mapping? living.attackTicks > 0 || */ living.hurtTime > 0 || living.activeEffects.size() > 0 )
++            if ( living.onClimbable() || living.jumping || living.hurtTime > 0 || living.activeEffects.size() > 0 ) // Paper
+             {
+-                return true;
++                return 1; // Paper
+             }
+-            if ( entity instanceof PathfinderMob && ( (PathfinderMob) entity ).getTarget() != null )
++            if ( entity instanceof Mob && ((Mob) entity ).getTarget() != null) // Paper
+             {
+-                return true;
++                return 20; // Paper
++            }
++            // Paper start
++            if (entity instanceof Bee) {
++                Bee bee = (Bee)entity;
++                BlockPos movingTarget = bee.getMovingTarget();
++                if (bee.isAngry() ||
++                    (bee.getHivePos() != null && bee.getHivePos().equals(movingTarget)) ||
++                    (bee.getSavedFlowerPos() != null && bee.getSavedFlowerPos().equals(movingTarget))
++                ) {
++                    return 20;
++                }
++            }
++            if ( entity instanceof Villager ) {
++                Brain<Villager> behaviorController = ((Villager) entity).getBrain();
++
++                if (config.villagersActiveForPanic) {
++                    for (Activity activity : VILLAGER_PANIC_IMMUNITIES) {
++                        if (behaviorController.isActive(activity)) {
++                            return 20*5;
++                        }
++                    }
++                }
++
++                if (config.villagersWorkImmunityAfter > 0 && inactiveFor >= config.villagersWorkImmunityAfter) {
++                    if (behaviorController.isActive(Activity.WORK)) {
++                        return config.villagersWorkImmunityFor;
++                    }
++                }
+             }
+-            if ( entity instanceof Villager && ( (Villager) entity ).canBreed() )
++            if ( entity instanceof Llama && ( (Llama) entity ).inCaravan() )
+             {
+-                return true;
++                return 1;
+             }
++            // Paper end
+             if ( entity instanceof Animal )
+             {
+                 Animal animal = (Animal) entity;
+                 if ( animal.isBaby() || animal.isInLove() )
+                 {
+-                    return true;
++                    return 5; // Paper
+                 }
+                 if ( entity instanceof Sheep && ( (Sheep) entity ).isSheared() )
+                 {
+-                    return true;
++                    return 1; // Paper
+                 }
+             }
+             if (entity instanceof Creeper && ((Creeper) entity).isIgnited()) { // isExplosive
+-                return true;
++                return 20; // Paper
++            }
++            // Paper start
++            if (entity instanceof Mob && ((Mob) entity).targetSelector.hasTasks() ) {
++                return 0;
+             }
++            if (entity instanceof Pillager) {
++                Pillager pillager = (Pillager) entity;
++                // TODO:?
++            }
++            // Paper end
+         }
+         // SPIGOT-6644: Otherwise the target refresh tick will be missed
+         if (entity instanceof ExperienceOrb) {
+-            return true;
++            return 20; // Paper
+         }
+-        return false;
++        return -1; // Paper
+     }
+ 
+     /**
+@@ -240,8 +376,19 @@ public class ActivationRange
+         if ( entity instanceof FireworkRocketEntity ) {
+             return true;
+         }
++        // Paper start - special case always immunities
++        // immunize brand new entities, dead entities, and portal scenarios
++        if (entity.defaultActivationState || entity.tickCount < 20*10 || !entity.isAlive() || entity.isInsidePortal || entity.portalCooldown > 0) {
++            return true;
++        }
++        // immunize leashed entities
++        if (entity instanceof Mob && ((Mob)entity).leashHolder instanceof Player) {
++            return true;
++        }
++        // Paper end
+ 
+-        boolean isActive = entity.activatedTick >= MinecraftServer.currentTick || entity.defaultActivationState;
++        boolean isActive = entity.activatedTick >= MinecraftServer.currentTick;
++        entity.isTemporarilyActive = false; // Paper
+ 
+         // Should this entity tick?
+         if ( !isActive )
+@@ -249,15 +396,19 @@ public class ActivationRange
+             if ( ( MinecraftServer.currentTick - entity.activatedTick - 1 ) % 20 == 0 )
+             {
+                 // Check immunities every 20 ticks.
+-                if ( ActivationRange.checkEntityImmunities( entity ) )
+-                {
+-                    // Triggered some sort of immunity, give 20 full ticks before we check again.
+-                    entity.activatedTick = MinecraftServer.currentTick + 20;
++                // Paper start
++                int immunity = checkEntityImmunities(entity);
++                if (immunity >= 0) {
++                    entity.activatedTick = MinecraftServer.currentTick + immunity;
++                } else {
++                    entity.isTemporarilyActive = true;
+                 }
++                // Paper end
+                 isActive = true;
++
+             }
+             // Add a little performance juice to active entities. Skip 1/4 if not immune.
+-        } else if ( !entity.defaultActivationState && entity.tickCount + entity.getId() + 1 % 4 == 0 && !ActivationRange.checkEntityImmunities( entity ) ) // Paper - Ensure checking item movement is offset from Spigot's entity activation range check
++        } else if ( entity.tickCount + entity.getId() + 1 % 4 == 0 && ActivationRange.checkEntityImmunities( entity ) < 0 ) // Paper
+         {
+             isActive = false;
+         }
+diff --git a/src/main/java/org/spigotmc/SpigotWorldConfig.java b/src/main/java/org/spigotmc/SpigotWorldConfig.java
+index d4d2d11cf19167410ec6ad3417495e7130330d11..9c9723e13b5440d4803a7268057d63cbdc973b77 100644
+--- a/src/main/java/org/spigotmc/SpigotWorldConfig.java
++++ b/src/main/java/org/spigotmc/SpigotWorldConfig.java
+@@ -199,14 +199,60 @@ public class SpigotWorldConfig
+     public int monsterActivationRange = 32;
+     public int raiderActivationRange = 48;
+     public int miscActivationRange = 16;
++    // Paper start
++    public int flyingMonsterActivationRange = 32;
++    public int waterActivationRange = 16;
++    public int villagerActivationRange = 32;
++    public int wakeUpInactiveAnimals = 4;
++    public int wakeUpInactiveAnimalsEvery = 60*20;
++    public int wakeUpInactiveAnimalsFor = 5*20;
++    public int wakeUpInactiveMonsters = 8;
++    public int wakeUpInactiveMonstersEvery = 20*20;
++    public int wakeUpInactiveMonstersFor = 5*20;
++    public int wakeUpInactiveVillagers = 4;
++    public int wakeUpInactiveVillagersEvery = 30*20;
++    public int wakeUpInactiveVillagersFor = 5*20;
++    public int wakeUpInactiveFlying = 8;
++    public int wakeUpInactiveFlyingEvery = 10*20;
++    public int wakeUpInactiveFlyingFor = 5*20;
++    public int villagersWorkImmunityAfter = 5*20;
++    public int villagersWorkImmunityFor = 20;
++    public boolean villagersActiveForPanic = true;
++    // Paper end
+     public boolean tickInactiveVillagers = true;
+     public boolean ignoreSpectatorActivation = false;
+     private void activationRange()
+     {
++        boolean hasAnimalsConfig = config.getInt("entity-activation-range.animals", this.animalActivationRange) != this.animalActivationRange; // Paper
+         this.animalActivationRange = this.getInt( "entity-activation-range.animals", this.animalActivationRange );
+         this.monsterActivationRange = this.getInt( "entity-activation-range.monsters", this.monsterActivationRange );
+         this.raiderActivationRange = this.getInt( "entity-activation-range.raiders", this.raiderActivationRange );
+         this.miscActivationRange = this.getInt( "entity-activation-range.misc", this.miscActivationRange );
++        // Paper start
++        this.waterActivationRange = this.getInt( "entity-activation-range.water", this.waterActivationRange );
++        this.villagerActivationRange = this.getInt( "entity-activation-range.villagers", hasAnimalsConfig ? this.animalActivationRange : this.villagerActivationRange );
++        this.flyingMonsterActivationRange = this.getInt( "entity-activation-range.flying-monsters", this.flyingMonsterActivationRange );
++
++        this.wakeUpInactiveAnimals = this.getInt("entity-activation-range.wake-up-inactive.animals-max-per-tick", this.wakeUpInactiveAnimals);
++        this.wakeUpInactiveAnimalsEvery = this.getInt("entity-activation-range.wake-up-inactive.animals-every", this.wakeUpInactiveAnimalsEvery);
++        this.wakeUpInactiveAnimalsFor = this.getInt("entity-activation-range.wake-up-inactive.animals-for", this.wakeUpInactiveAnimalsFor);
++
++        this.wakeUpInactiveMonsters = this.getInt("entity-activation-range.wake-up-inactive.monsters-max-per-tick", this.wakeUpInactiveMonsters);
++        this.wakeUpInactiveMonstersEvery = this.getInt("entity-activation-range.wake-up-inactive.monsters-every", this.wakeUpInactiveMonstersEvery);
++        this.wakeUpInactiveMonstersFor = this.getInt("entity-activation-range.wake-up-inactive.monsters-for", this.wakeUpInactiveMonstersFor);
++
++        this.wakeUpInactiveVillagers = this.getInt("entity-activation-range.wake-up-inactive.villagers-max-per-tick", this.wakeUpInactiveVillagers);
++        this.wakeUpInactiveVillagersEvery = this.getInt("entity-activation-range.wake-up-inactive.villagers-every", this.wakeUpInactiveVillagersEvery);
++        this.wakeUpInactiveVillagersFor = this.getInt("entity-activation-range.wake-up-inactive.villagers-for", this.wakeUpInactiveVillagersFor);
++
++        this.wakeUpInactiveFlying = this.getInt("entity-activation-range.wake-up-inactive.flying-monsters-max-per-tick", this.wakeUpInactiveFlying);
++        this.wakeUpInactiveFlyingEvery = this.getInt("entity-activation-range.wake-up-inactive.flying-monsters-every", this.wakeUpInactiveFlyingEvery);
++        this.wakeUpInactiveFlyingFor = this.getInt("entity-activation-range.wake-up-inactive.flying-monsters-for", this.wakeUpInactiveFlyingFor);
++
++        this.villagersWorkImmunityAfter = this.getInt( "entity-activation-range.villagers-work-immunity-after", this.villagersWorkImmunityAfter );
++        this.villagersWorkImmunityFor = this.getInt( "entity-activation-range.villagers-work-immunity-for", this.villagersWorkImmunityFor );
++        this.villagersActiveForPanic = this.getBoolean( "entity-activation-range.villagers-active-for-panic", this.villagersActiveForPanic );
++        // Paper end
+         this.tickInactiveVillagers = this.getBoolean( "entity-activation-range.tick-inactive-villagers", this.tickInactiveVillagers );
+         this.ignoreSpectatorActivation = this.getBoolean( "entity-activation-range.ignore-spectators", this.ignoreSpectatorActivation );
+         this.log( "Entity Activation Range: An " + this.animalActivationRange + " / Mo " + this.monsterActivationRange + " / Ra " + this.raiderActivationRange + " / Mi " + this.miscActivationRange + " / Tiv " + this.tickInactiveVillagers + " / Isa " + this.ignoreSpectatorActivation );