Reduce MutableInt and Vec3d allocations, use ArrayDeque

Spigot-Server-Patches/ChunkMapDistance-CME.patch

@@ -13,7 +13,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
      private final ChunkMapDistance.b f = new ChunkMapDistance.b(8);
      private final ChunkMapDistance.c g = new ChunkMapDistance.c(33);
 -    private final Set<PlayerChunk> pendingChunkUpdates = Sets.newHashSet();
-+    private final java.util.Queue<PlayerChunk> pendingChunkUpdates = new java.util.LinkedList<>(); // PAIL pendingChunkUpdates // Paper - use a queue
++    private final java.util.Queue<PlayerChunk> pendingChunkUpdates = new java.util.ArrayDeque<>(); // PAIL pendingChunkUpdates // Paper - use a queue
      private final ChunkTaskQueueSorter i;
      private final Mailbox<ChunkTaskQueueSorter.a<Runnable>> j;
      private final Mailbox<ChunkTaskQueueSorter.b> k;

Spigot-Server-Patches/Optimize-isOutsideRange-to-use-distance-maps.patch

@@ -16,7 +16,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 -    private final ChunkMapDistance.b f = new ChunkMapDistance.b(8);
 +    public static final int MOB_SPAWN_RANGE = 8; //private final ChunkMapDistance.b f = new ChunkMapDistance.b(8); // Paper - no longer used
      private final ChunkMapDistance.c g = new ChunkMapDistance.c(33);
-     private final java.util.Queue<PlayerChunk> pendingChunkUpdates = new java.util.LinkedList<>(); // PAIL pendingChunkUpdates // Paper - use a queue
+     private final java.util.Queue<PlayerChunk> pendingChunkUpdates = new java.util.ArrayDeque<>(); // PAIL pendingChunkUpdates // Paper - use a queue
      private final ChunkTaskQueueSorter i;
 @@ -0,0 +0,0 @@ public abstract class ChunkMapDistance {
      private final Executor m;

Spigot-Server-Patches/Reduce-MutableInt-allocations-from-light-engine.patch

@@ -0,0 +1,60 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Spottedleaf <spottedleaf@spottedleaf.dev>
+Date: Mon, 27 Apr 2020 02:48:06 -0700
+Subject: [PATCH] Reduce MutableInt allocations from light engine
+
+
+diff --git a/src/main/java/net/minecraft/server/LightEngineBlock.java b/src/main/java/net/minecraft/server/LightEngineBlock.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/net/minecraft/server/LightEngineBlock.java
++++ b/src/main/java/net/minecraft/server/LightEngineBlock.java
+@@ -0,0 +0,0 @@ public final class LightEngineBlock extends LightEngineLayer<LightEngineStorageB
+             if (enumdirection == null) {
+                 return 15;
+             } else {
+-                MutableInt mutableint = new MutableInt();
++                // Paper start - reduce mutableint allocations
++                MutableInt mutableint = com.destroystokyo.paper.util.pooled.PooledObjects.POOLED_MUTABLE_INTEGERS.acquire();
++                try {
++                // Paper end - reduce mutableint allocations
+                 IBlockData iblockdata = this.a(j, mutableint);
+ 
+                 if (mutableint.getValue() >= 15) {
+@@ -0,0 +0,0 @@ public final class LightEngineBlock extends LightEngineLayer<LightEngineStorageB
+ 
+                     return VoxelShapes.b(voxelshape, voxelshape1) ? 15 : k + Math.max(1, mutableint.getValue());
+                 }
++                } finally { // Paper start - reduce mutableint allocations
++                    com.destroystokyo.paper.util.pooled.PooledObjects.POOLED_MUTABLE_INTEGERS.release(mutableint);
++                }
++                // Paper end - reduce mutableint allocations
+             }
+         }
+     }
+diff --git a/src/main/java/net/minecraft/server/LightEngineSky.java b/src/main/java/net/minecraft/server/LightEngineSky.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/net/minecraft/server/LightEngineSky.java
++++ b/src/main/java/net/minecraft/server/LightEngineSky.java
+@@ -0,0 +0,0 @@ public final class LightEngineSky extends LightEngineLayer<LightEngineStorageSky
+             if (k >= 15) {
+                 return k;
+             } else {
+-                MutableInt mutableint = new MutableInt();
++                // Paper start - reduce mutableint allocations
++                MutableInt mutableint = com.destroystokyo.paper.util.pooled.PooledObjects.POOLED_MUTABLE_INTEGERS.acquire();
++                try {
++                // Paper end - reduce mutableint allocations
+                 IBlockData iblockdata = this.a(j, mutableint);
+ 
+                 if (mutableint.getValue() >= 15) {
+@@ -0,0 +0,0 @@ public final class LightEngineSky extends LightEngineLayer<LightEngineStorageSky
+ 
+                     return flag1 && k == 0 && mutableint.getValue() == 0 ? 0 : k + Math.max(1, mutableint.getValue());
+                 }
++                } finally { // Paper start - reduce mutableint allocations
++                    com.destroystokyo.paper.util.pooled.PooledObjects.POOLED_MUTABLE_INTEGERS.release(mutableint);
++                }
++                // Paper end - reduce mutableint allocations
+             }
+         }
+     }

Spigot-Server-Patches/Reduce-allocation-of-Vec3D-by-entity-tracker.patch

@@ -0,0 +1,61 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Spottedleaf <spottedleaf@spottedleaf.dev>
+Date: Mon, 27 Apr 2020 00:04:16 -0700
+Subject: [PATCH] Reduce allocation of Vec3D by entity tracker
+
+
+diff --git a/src/main/java/net/minecraft/server/EntityTrackerEntry.java b/src/main/java/net/minecraft/server/EntityTrackerEntry.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/net/minecraft/server/EntityTrackerEntry.java
++++ b/src/main/java/net/minecraft/server/EntityTrackerEntry.java
+@@ -0,0 +0,0 @@ public class EntityTrackerEntry {
+                 ++this.o;
+                 i = MathHelper.d(this.tracker.yaw * 256.0F / 360.0F);
+                 j = MathHelper.d(this.tracker.pitch * 256.0F / 360.0F);
+-                Vec3D vec3d = this.tracker.getPositionVector().d(PacketPlayOutEntity.a(this.xLoc, this.yLoc, this.zLoc));
+-                boolean flag1 = vec3d.g() >= 7.62939453125E-6D;
++                // Paper start - reduce allocation of Vec3D here
++                double vec3d_dx = this.tracker.locX() - 2.44140625E-4D*(this.xLoc);
++                double vec3d_dy = this.tracker.locY() - 2.44140625E-4D*(this.yLoc);
++                double vec3d_dz = this.tracker.locZ() - 2.44140625E-4D*(this.zLoc);
++                boolean flag1 = (vec3d_dx * vec3d_dx + vec3d_dy * vec3d_dy + vec3d_dz * vec3d_dz) >= 7.62939453125E-6D;
++                // Paper end - reduce allocation of Vec3D here
+                 Packet<?> packet1 = null;
+                 boolean flag2 = flag1 || this.tickCounter % 60 == 0;
+                 boolean flag3 = Math.abs(i - this.yRot) >= 1 || Math.abs(j - this.xRot) >= 1;
+@@ -0,0 +0,0 @@ public class EntityTrackerEntry {
+                 // CraftBukkit end
+ 
+                 if (this.tickCounter > 0 || this.tracker instanceof EntityArrow) {
+-                    long k = PacketPlayOutEntity.a(vec3d.x);
+-                    long l = PacketPlayOutEntity.a(vec3d.y);
+-                    long i1 = PacketPlayOutEntity.a(vec3d.z);
++                    // Paper start - remove allocation of Vec3D here
++                    long k = PacketPlayOutEntity.a(vec3d_dx);
++                    long l = PacketPlayOutEntity.a(vec3d_dy);
++                    long i1 = PacketPlayOutEntity.a(vec3d_dz);
++                    // Paper end - remove allocation of Vec3D here
+                     boolean flag4 = k < -32768L || k > 32767L || l < -32768L || l > 32767L || i1 < -32768L || i1 > 32767L;
+ 
+                     if (!flag4 && this.o <= 400 && !this.q && this.r == this.tracker.onGround) {
+diff --git a/src/main/java/net/minecraft/server/PlayerChunkMap.java b/src/main/java/net/minecraft/server/PlayerChunkMap.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/net/minecraft/server/PlayerChunkMap.java
++++ b/src/main/java/net/minecraft/server/PlayerChunkMap.java
+@@ -0,0 +0,0 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+         public void updatePlayer(EntityPlayer entityplayer) {
+             org.spigotmc.AsyncCatcher.catchOp("player tracker update"); // Spigot
+             if (entityplayer != this.tracker) {
+-                Vec3D vec3d = entityplayer.getPositionVector().d(this.tracker.getPositionVector()); // MC-155077, SPIGOT-5113
++                // Paper start - remove allocation of Vec3D here
++                //Vec3D vec3d = entityplayer.getPositionVector().d(this.tracker.getPositionVector()); // MC-155077, SPIGOT-5113
++                double vec3d_dx = entityplayer.locX() - this.tracker.locX();
++                double vec3d_dy = entityplayer.locY() - this.tracker.locY();
++                double vec3d_dz = entityplayer.locZ() - this.tracker.locZ();
++                // Paper end - remove allocation of Vec3D here
+                 int i = Math.min(this.b(), (PlayerChunkMap.this.viewDistance - 1) * 16);
+-                boolean flag = vec3d.x >= (double) (-i) && vec3d.x <= (double) i && vec3d.z >= (double) (-i) && vec3d.z <= (double) i && this.tracker.a(entityplayer);
++                boolean flag = vec3d_dx >= (double) (-i) && vec3d_dx <= (double) i && vec3d_dz >= (double) (-i) && vec3d_dz <= (double) i && this.tracker.a(entityplayer); // Paper - remove allocation of Vec3D here
+ 
+                 if (flag) {
+                     boolean flag1 = this.tracker.attachedToPlayer;