Remove MOST Synchronization from Chunk Map

This will provide quite a major performance boost by avoiding
synchronizing on EVERY chunk lookup.

Synchronize, even without contention, incurs processor cache flushes.

Considering this is the 2nd hottest method in the code base, lets
avoid doing that...

Additionally, chunk conversion operations were occuring while
under synchronization which lead to deadlocks.

Now the conversion will occur outside of the lock, and fix
that issue, resolving #1586

Note, that the chunk map is still thread safe for get operations!

The chunk map was never intended to be modified async with our
changes, as we post to main to modify the map, however
we do still synchronize for write operations (put, remove)

We also synchronize for async get operations, ensuring that
async gets are safe.

We do not need to synchronize main thread gets as the processor
cache will be insync since the map is only updated on the main thread.

However, if someone does try to delete or put concurrently, we
will force their operation back to the main thread.

Spigot-Server-Patches/Add-Velocity-IP-Forwarding-Support.patch

@@ -14,7 +14,7 @@ forwarding, and is integrated into the Minecraft login process by using the 1.13
 login plugin message packet.
 
 diff --git a/src/main/java/com/destroystokyo/paper/PaperConfig.java b/src/main/java/com/destroystokyo/paper/PaperConfig.java
-index 352166725..70f650bb2 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/com/destroystokyo/paper/PaperConfig.java
 +++ b/src/main/java/com/destroystokyo/paper/PaperConfig.java
 @@ -0,0 +0,0 @@ import java.io.IOException;
@@ -55,7 +55,7 @@ index 352166725..70f650bb2 100644
  }
 diff --git a/src/main/java/com/destroystokyo/paper/proxy/VelocityProxy.java b/src/main/java/com/destroystokyo/paper/proxy/VelocityProxy.java
 new file mode 100644
-index 000000000..fdd8708f9
+index 7ac07ac07ac0..7ac07ac07ac0
 --- /dev/null
 +++ b/src/main/java/com/destroystokyo/paper/proxy/VelocityProxy.java
 @@ -0,0 +0,0 @@
@@ -127,7 +127,7 @@ index 000000000..fdd8708f9
 +    }
 +}
 diff --git a/src/main/java/net/minecraft/server/LoginListener.java b/src/main/java/net/minecraft/server/LoginListener.java
-index 5778a5201..b6a3992a3 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/LoginListener.java
 +++ b/src/main/java/net/minecraft/server/LoginListener.java
 @@ -0,0 +0,0 @@ public class LoginListener implements PacketLoginInListener, ITickable {
@@ -203,7 +203,7 @@ index 5778a5201..b6a3992a3 100644
      }
  
 diff --git a/src/main/java/net/minecraft/server/NetworkManager.java b/src/main/java/net/minecraft/server/NetworkManager.java
-index b2afec5e4..97a9dffe6 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/NetworkManager.java
 +++ b/src/main/java/net/minecraft/server/NetworkManager.java
 @@ -0,0 +0,0 @@ public class NetworkManager extends SimpleChannelInboundHandler<Packet<?>> {
@@ -216,7 +216,7 @@ index b2afec5e4..97a9dffe6 100644
      public com.mojang.authlib.properties.Property[] spoofedProfile;
      public boolean preparing = true;
 diff --git a/src/main/java/net/minecraft/server/PacketDataSerializer.java b/src/main/java/net/minecraft/server/PacketDataSerializer.java
-index cab837483..fb6e373f0 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/PacketDataSerializer.java
 +++ b/src/main/java/net/minecraft/server/PacketDataSerializer.java
 @@ -0,0 +0,0 @@ public class PacketDataSerializer extends ByteBuf {
@@ -244,7 +244,7 @@ index cab837483..fb6e373f0 100644
          int j = this.g();
  
 diff --git a/src/main/java/net/minecraft/server/PacketLoginInCustomPayload.java b/src/main/java/net/minecraft/server/PacketLoginInCustomPayload.java
-index e3c0094f7..edfd4a506 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/PacketLoginInCustomPayload.java
 +++ b/src/main/java/net/minecraft/server/PacketLoginInCustomPayload.java
 @@ -0,0 +0,0 @@ package net.minecraft.server;
@@ -259,7 +259,7 @@ index e3c0094f7..edfd4a506 100644
      public PacketLoginInCustomPayload() {
      }
 diff --git a/src/main/java/net/minecraft/server/PacketLoginOutCustomPayload.java b/src/main/java/net/minecraft/server/PacketLoginOutCustomPayload.java
-index 9c5559ece..9de0421bb 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/PacketLoginOutCustomPayload.java
 +++ b/src/main/java/net/minecraft/server/PacketLoginOutCustomPayload.java
 @@ -0,0 +0,0 @@ public class PacketLoginOutCustomPayload implements Packet<PacketLoginOutListene

Spigot-Server-Patches/Async-Chunk-Loading-and-Generation.patch

@@ -43,7 +43,7 @@ reading or writing to the chunk will be safe, so plugins still
 should not be touching chunks asynchronously!
 
 diff --git a/src/main/java/com/destroystokyo/paper/PaperConfig.java b/src/main/java/com/destroystokyo/paper/PaperConfig.java
-index b703e0848..77d35ac99 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/com/destroystokyo/paper/PaperConfig.java
 +++ b/src/main/java/com/destroystokyo/paper/PaperConfig.java
 @@ -0,0 +0,0 @@ public class PaperConfig {
@@ -106,7 +106,7 @@ index b703e0848..77d35ac99 100644
  }
 diff --git a/src/main/java/com/destroystokyo/paper/util/PriorityQueuedExecutor.java b/src/main/java/com/destroystokyo/paper/util/PriorityQueuedExecutor.java
 new file mode 100644
-index 000000000..5c77b6e8e
+index 7ac07ac07ac0..7ac07ac07ac0
 --- /dev/null
 +++ b/src/main/java/com/destroystokyo/paper/util/PriorityQueuedExecutor.java
 @@ -0,0 +0,0 @@
@@ -392,7 +392,7 @@ index 000000000..5c77b6e8e
 +
 +}
 diff --git a/src/main/java/net/minecraft/server/Chunk.java b/src/main/java/net/minecraft/server/Chunk.java
-index edfcb107b..cb9988870 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/Chunk.java
 +++ b/src/main/java/net/minecraft/server/Chunk.java
 @@ -0,0 +0,0 @@ public class Chunk implements IChunkAccess {
@@ -403,12 +403,122 @@ index edfcb107b..cb9988870 100644
          }
  
          Iterator iterator = protochunk.s().iterator();
+diff --git a/src/main/java/net/minecraft/server/ChunkMap.java b/src/main/java/net/minecraft/server/ChunkMap.java
+index 7ac07ac07ac0..7ac07ac07ac0 100644
+--- a/src/main/java/net/minecraft/server/ChunkMap.java
++++ b/src/main/java/net/minecraft/server/ChunkMap.java
+@@ -0,0 +0,0 @@ public class ChunkMap extends Long2ObjectOpenHashMap<Chunk> {
+     }
+ 
+     public Chunk a(long i, Chunk chunk) {
++        org.spigotmc.AsyncCatcher.catchOp("Async Chunk put"); // Paper
+         chunk.world.timings.syncChunkLoadPostTimer.startTiming(); // Paper
+         lastChunkByPos = chunk; // Paper
+-        Chunk chunk1 = (Chunk) super.put(i, chunk);
++        // Paper start
++        Chunk chunk1;
++        synchronized (this) {
++            // synchronize so any async gets are safe
++            chunk1 = (Chunk) super.put(i, chunk);
++        }
++        if (chunk1 == null) { // Paper - we should never be overwriting chunks
++        // Paper end
+         ChunkCoordIntPair chunkcoordintpair = new ChunkCoordIntPair(i);
+ 
+         for (int j = chunkcoordintpair.x - 1; j <= chunkcoordintpair.x + 1; ++j) {
+@@ -0,0 +0,0 @@ public class ChunkMap extends Long2ObjectOpenHashMap<Chunk> {
+                     chunk.setNeighborLoaded(x, z);
+                 }
+             }
++            // Paper start
++        } } else {
++            a.error("Overwrote existing chunk! (" + chunk.world.getWorld().getName() + ":" + chunk.locX+"," + chunk.locZ + ")", new IllegalStateException());
+         }
++        // Paper end
+         // Paper start - if this is a spare chunk (not part of any players view distance), go ahead and queue it for unload.
+         if (!((WorldServer)chunk.world).getPlayerChunkMap().isChunkInUse(chunk.locX, chunk.locZ)) {
+             if (chunk.world.paperConfig.delayChunkUnloadsBy > 0) {
+@@ -0,0 +0,0 @@ public class ChunkMap extends Long2ObjectOpenHashMap<Chunk> {
+     }
+ 
+     public Chunk a(Long olong, Chunk chunk) {
+-        return this.a(olong.longValue(), chunk);
++        return MCUtil.ensureMain("Chunk Put", () -> this.a(olong.longValue(), chunk)); // Paper
+     }
+ 
+     public Chunk a(long i) {
+-        Chunk chunk = (Chunk) super.remove(i);
++        // Paper start
++        org.spigotmc.AsyncCatcher.catchOp("Async Chunk remove");
++        Chunk chunk;
++        synchronized (this) {
++            // synchronize so any async gets are safe
++            chunk = super.remove(i);
++        }
++        if (chunk != null) { // Paper - don't decrement if we didn't remove anything
++        // Paper end
+         ChunkCoordIntPair chunkcoordintpair = new ChunkCoordIntPair(i);
+ 
+         for (int j = chunkcoordintpair.x - 1; j <= chunkcoordintpair.x + 1; ++j) {
+@@ -0,0 +0,0 @@ public class ChunkMap extends Long2ObjectOpenHashMap<Chunk> {
+         }
+ 
+         // Paper start
++        } // close if (chunk != null)
+         if (lastChunkByPos != null && i == lastChunkByPos.chunkKey) {
+             lastChunkByPos = null;
+         }
+@@ -0,0 +0,0 @@ public class ChunkMap extends Long2ObjectOpenHashMap<Chunk> {
+ 
+     @Override
+     public Chunk get(long l) {
+-        if (lastChunkByPos != null && l == lastChunkByPos.chunkKey) {
+-            return lastChunkByPos;
++        if (MCUtil.isMainThread()) {
++            if (lastChunkByPos != null && l == lastChunkByPos.chunkKey) {
++                return lastChunkByPos;
++            }
++            final Chunk chunk = super.get(l);
++            return chunk != null ? (lastChunkByPos = chunk) : null;
++        } else {
++            synchronized (this) {
++                return super.get(l);
++            }
+         }
+-        return lastChunkByPos = super.get(l);
+     }
+     // Paper end
+ 
+     public Chunk a(Object object) {
+-        return this.a(((Long) object).longValue());
++        return MCUtil.ensureMain("Chunk Remove", () -> this.a(((Long) object).longValue())); // Paper
+     }
+ 
+     public void putAll(Map<? extends Long, ? extends Chunk> map) {
+@@ -0,0 +0,0 @@ public class ChunkMap extends Long2ObjectOpenHashMap<Chunk> {
+ 
+     // CraftBukkit start - decompile errors
+     public Chunk remove(long i) {
+-        return this.a(i);
++        return MCUtil.ensureMain("Chunk Remove", () -> this.a(i)); // Paper
+     }
+ 
+     public Chunk put(long i, Chunk object) {
+-        return this.a(i, (Chunk) object);
++        return MCUtil.ensureMain("Chunk Put", () -> this.a(i, (Chunk) object)); // Paper
+     }
+ 
+     public Chunk remove(Object object) {
 diff --git a/src/main/java/net/minecraft/server/ChunkProviderServer.java b/src/main/java/net/minecraft/server/ChunkProviderServer.java
-index 958a4084e..56a76e17e 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/ChunkProviderServer.java
 +++ b/src/main/java/net/minecraft/server/ChunkProviderServer.java
 @@ -0,0 +0,0 @@ public class ChunkProviderServer implements IChunkProvider {
-     public final Long2ObjectMap<Chunk> chunks = Long2ObjectMaps.synchronize(new ChunkMap(8192));
+     private long lastProcessedSaves = 0L; // Paper
+     private long lastSaveStatPrinted = System.currentTimeMillis();
+     // Paper end
+-    public final Long2ObjectMap<Chunk> chunks = Long2ObjectMaps.synchronize(new ChunkMap(8192));
++    public final Long2ObjectMap<Chunk> chunks = new ChunkMap(8192); // Paper - remove synchronize - we keep everything on main for manip
      private Chunk lastChunk;
      private final ChunkTaskScheduler chunkScheduler;
 -    private final SchedulerBatch<ChunkCoordIntPair, ChunkStatus, ProtoChunk> batchScheduler;
@@ -550,7 +660,7 @@ index 958a4084e..56a76e17e 100644
      }
  
 diff --git a/src/main/java/net/minecraft/server/ChunkRegionLoader.java b/src/main/java/net/minecraft/server/ChunkRegionLoader.java
-index c233b7e90..edd074252 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/ChunkRegionLoader.java
 +++ b/src/main/java/net/minecraft/server/ChunkRegionLoader.java
 @@ -0,0 +0,0 @@ public class ChunkRegionLoader implements IChunkLoader, IAsyncChunkSaver {
@@ -577,7 +687,7 @@ index c233b7e90..edd074252 100644
                  completion = new Supplier<NBTTagCompound>() {
                      public NBTTagCompound get() {
 diff --git a/src/main/java/net/minecraft/server/ChunkSection.java b/src/main/java/net/minecraft/server/ChunkSection.java
-index bdfc7d81f..a5c4564d6 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/ChunkSection.java
 +++ b/src/main/java/net/minecraft/server/ChunkSection.java
 @@ -0,0 +0,0 @@ public class ChunkSection {
@@ -599,7 +709,7 @@ index bdfc7d81f..a5c4564d6 100644
      public IBlockData getType(int i, int j, int k) {
          return this.blockIds.a(i, j, k);
 diff --git a/src/main/java/net/minecraft/server/ChunkTaskScheduler.java b/src/main/java/net/minecraft/server/ChunkTaskScheduler.java
-index 34019bd1b..fc9091c80 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/ChunkTaskScheduler.java
 +++ b/src/main/java/net/minecraft/server/ChunkTaskScheduler.java
 @@ -0,0 +0,0 @@ public class ChunkTaskScheduler extends Scheduler<ChunkCoordIntPair, ChunkStatus
@@ -670,7 +780,7 @@ index 34019bd1b..fc9091c80 100644
  
      protected ProtoChunk a(ChunkCoordIntPair chunkcoordintpair, ChunkStatus chunkstatus, Map<ChunkCoordIntPair, ProtoChunk> map) {
 diff --git a/src/main/java/net/minecraft/server/DataPaletteBlock.java b/src/main/java/net/minecraft/server/DataPaletteBlock.java
-index 71a3636be..ff0fe2541 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/DataPaletteBlock.java
 +++ b/src/main/java/net/minecraft/server/DataPaletteBlock.java
 @@ -0,0 +0,0 @@ package net.minecraft.server;
@@ -755,7 +865,7 @@ index 71a3636be..ff0fe2541 100644
  
      // Paper start - Anti-Xray - Support default methods
 diff --git a/src/main/java/net/minecraft/server/DefinedStructureManager.java b/src/main/java/net/minecraft/server/DefinedStructureManager.java
-index 271dc41d4..bd15534c2 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/DefinedStructureManager.java
 +++ b/src/main/java/net/minecraft/server/DefinedStructureManager.java
 @@ -0,0 +0,0 @@ import org.apache.logging.log4j.Logger;
@@ -768,7 +878,7 @@ index 271dc41d4..bd15534c2 100644
      private final MinecraftServer d;
      private final java.nio.file.Path e;
 diff --git a/src/main/java/net/minecraft/server/Entity.java b/src/main/java/net/minecraft/server/Entity.java
-index 0237049a4..cd601f29a 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/Entity.java
 +++ b/src/main/java/net/minecraft/server/Entity.java
 @@ -0,0 +0,0 @@ public abstract class Entity implements INamableTileEntity, ICommandListener, Ke
@@ -781,7 +891,7 @@ index 0237049a4..cd601f29a 100644
          this.aJ = Sets.newHashSet();
          this.aL = new double[] { 0.0D, 0.0D, 0.0D};
 diff --git a/src/main/java/net/minecraft/server/IChunkLoader.java b/src/main/java/net/minecraft/server/IChunkLoader.java
-index 4698ee99f..dfb45cc4e 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/IChunkLoader.java
 +++ b/src/main/java/net/minecraft/server/IChunkLoader.java
 @@ -0,0 +0,0 @@ import javax.annotation.Nullable;
@@ -794,7 +904,7 @@ index 4698ee99f..dfb45cc4e 100644
      Chunk a(GeneratorAccess generatoraccess, int i, int j, Consumer<Chunk> consumer) throws IOException;
  
 diff --git a/src/main/java/net/minecraft/server/MathHelper.java b/src/main/java/net/minecraft/server/MathHelper.java
-index 49fba0979..9ad646f8d 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/MathHelper.java
 +++ b/src/main/java/net/minecraft/server/MathHelper.java
 @@ -0,0 +0,0 @@ public class MathHelper {
@@ -806,7 +916,7 @@ index 49fba0979..9ad646f8d 100644
          fx = fx % 360.0F;
          if (fx >= 180.0F) {
 diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
-index 98d182fdb..487d98eb1 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/MinecraftServer.java
 +++ b/src/main/java/net/minecraft/server/MinecraftServer.java
 @@ -0,0 +0,0 @@ public abstract class MinecraftServer implements IAsyncTaskHandler, IMojangStati
@@ -904,7 +1014,7 @@ index 98d182fdb..487d98eb1 100644
  
 diff --git a/src/main/java/net/minecraft/server/PaperAsyncChunkProvider.java b/src/main/java/net/minecraft/server/PaperAsyncChunkProvider.java
 new file mode 100644
-index 000000000..5823917a6
+index 7ac07ac07ac0..7ac07ac07ac0
 --- /dev/null
 +++ b/src/main/java/net/minecraft/server/PaperAsyncChunkProvider.java
 @@ -0,0 +0,0 @@
@@ -1502,7 +1612,7 @@ index 000000000..5823917a6
 +
 +}
 diff --git a/src/main/java/net/minecraft/server/PlayerChunk.java b/src/main/java/net/minecraft/server/PlayerChunk.java
-index 2c7c8adf7..aabd107fe 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/PlayerChunk.java
 +++ b/src/main/java/net/minecraft/server/PlayerChunk.java
 @@ -0,0 +0,0 @@ public class PlayerChunk {
@@ -1607,7 +1717,7 @@ index 2c7c8adf7..aabd107fe 100644
          }
      }
 diff --git a/src/main/java/net/minecraft/server/PlayerChunkMap.java b/src/main/java/net/minecraft/server/PlayerChunkMap.java
-index d1a443ca8..1504bd113 100644
+index 7ac07ac07ac0..7ac07ac07ac0 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 {
@@ -1667,7 +1777,7 @@ index d1a443ca8..1504bd113 100644
  
      private void e() {
 diff --git a/src/main/java/net/minecraft/server/RegionLimitedWorldAccess.java b/src/main/java/net/minecraft/server/RegionLimitedWorldAccess.java
-index 3c35c0f48..187ca2813 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/RegionLimitedWorldAccess.java
 +++ b/src/main/java/net/minecraft/server/RegionLimitedWorldAccess.java
 @@ -0,0 +0,0 @@ public class RegionLimitedWorldAccess implements GeneratorAccess {
@@ -1680,7 +1790,7 @@ index 3c35c0f48..187ca2813 100644
          this.m = world.getChunkProvider().getChunkGenerator().getSettings();
          this.i = world.getSeaLevel();
 diff --git a/src/main/java/net/minecraft/server/SchedulerBatch.java b/src/main/java/net/minecraft/server/SchedulerBatch.java
-index d868149d1..0d45d933e 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/SchedulerBatch.java
 +++ b/src/main/java/net/minecraft/server/SchedulerBatch.java
 @@ -0,0 +0,0 @@ public class SchedulerBatch<K, T extends SchedulerTask<K, T>, R> {
@@ -1735,7 +1845,7 @@ index d868149d1..0d45d933e 100644
      }
  }
 diff --git a/src/main/java/net/minecraft/server/StructurePiece.java b/src/main/java/net/minecraft/server/StructurePiece.java
-index a5cf017da..def8730b8 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/StructurePiece.java
 +++ b/src/main/java/net/minecraft/server/StructurePiece.java
 @@ -0,0 +0,0 @@ public abstract class StructurePiece {
@@ -1762,7 +1872,7 @@ index a5cf017da..def8730b8 100644
          return null;
      }
 diff --git a/src/main/java/net/minecraft/server/StructureStart.java b/src/main/java/net/minecraft/server/StructureStart.java
-index f87182b5c..574930f5f 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/StructureStart.java
 +++ b/src/main/java/net/minecraft/server/StructureStart.java
 @@ -0,0 +0,0 @@ import java.util.List;
@@ -1811,7 +1921,7 @@ index f87182b5c..574930f5f 100644
      }
  
 diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
-index a2559f0c1..bbcedb8fc 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/World.java
 +++ b/src/main/java/net/minecraft/server/World.java
 @@ -0,0 +0,0 @@ import org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason;
@@ -1908,7 +2018,7 @@ index a2559f0c1..bbcedb8fc 100644
          if (entity == null) return false;
          if (entity.valid) { MinecraftServer.LOGGER.error("Attempted Double World add on " + entity, new Throwable()); return true; } // Paper
 diff --git a/src/main/java/net/minecraft/server/WorldGenStronghold.java b/src/main/java/net/minecraft/server/WorldGenStronghold.java
-index fa99fe014..4f49786aa 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/WorldGenStronghold.java
 +++ b/src/main/java/net/minecraft/server/WorldGenStronghold.java
 @@ -0,0 +0,0 @@ import java.util.Random;
@@ -2055,7 +2165,7 @@ index fa99fe014..4f49786aa 100644
                  }
              }
 diff --git a/src/main/java/net/minecraft/server/WorldServer.java b/src/main/java/net/minecraft/server/WorldServer.java
-index ad3fea9c9..0a7648263 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/WorldServer.java
 +++ b/src/main/java/net/minecraft/server/WorldServer.java
 @@ -0,0 +0,0 @@ public class WorldServer extends World implements IAsyncTaskHandler {
@@ -2068,7 +2178,7 @@ index ad3fea9c9..0a7648263 100644
      }
  
 diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
-index 9c7b86a55..206cb30f6 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
 +++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
 @@ -0,0 +0,0 @@ public final class CraftServer implements Server {
@@ -2096,7 +2206,7 @@ index 9c7b86a55..206cb30f6 100644
              }
          }
 diff --git a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
-index d0110070a..02b6bf299 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
 +++ b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
 @@ -0,0 +0,0 @@ public class CraftWorld implements World {
@@ -2134,7 +2244,7 @@ index d0110070a..02b6bf299 100644
                      if (isChunkLoaded(chunkCoordX + x, chunkCoordZ + z)) {
                          unloadChunk(chunkCoordX + x, chunkCoordZ + z);
 diff --git a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
-index 9e903159d..4ead18b66 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
 +++ b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
 @@ -0,0 +0,0 @@ public class CraftEventFactory {
@@ -2196,7 +2306,7 @@ index 9e903159d..4ead18b66 100644
  
          if (!event.isCancelled()) {
 diff --git a/src/main/java/org/bukkit/craftbukkit/generator/CustomChunkGenerator.java b/src/main/java/org/bukkit/craftbukkit/generator/CustomChunkGenerator.java
-index 9c2adb235..62c197b80 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/org/bukkit/craftbukkit/generator/CustomChunkGenerator.java
 +++ b/src/main/java/org/bukkit/craftbukkit/generator/CustomChunkGenerator.java
 @@ -0,0 +0,0 @@ public class CustomChunkGenerator extends InternalChunkGenerator<GeneratorSettin

Spigot-Server-Patches/Call-player-spectator-target-events.patch

@@ -5,7 +5,7 @@ Subject: [PATCH] Call player spectator target events
 
 
 diff --git a/src/main/java/net/minecraft/server/EntityPlayer.java b/src/main/java/net/minecraft/server/EntityPlayer.java
-index 5ab4e01ed..4ca5cfe9a 100644
+index 7ac07ac07ac0..7ac07ac07ac0 100644
 --- a/src/main/java/net/minecraft/server/EntityPlayer.java
 +++ b/src/main/java/net/minecraft/server/EntityPlayer.java
 @@ -0,0 +0,0 @@ public class EntityPlayer extends EntityHuman implements ICrafting {

Spigot-Server-Patches/Ensure-chunk-neighbor-counts-do-not-get-desynced.patch

@@ -1,52 +0,0 @@
-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
-From: Aikar <aikar@aikar.co>
-Date: Wed, 17 Oct 2018 22:31:54 -0400
-Subject: [PATCH] Ensure chunk neighbor counts do not get desynced
-
-Mojang was not checking that the chunk did not overwrite, or
-was successfully removed.
-
-We're seeing odd reports in #1561 that indicates issues around
-this are having problems.
-
-diff --git a/src/main/java/net/minecraft/server/ChunkMap.java b/src/main/java/net/minecraft/server/ChunkMap.java
-index 39ac032b0b..1fb0770015 100644
---- a/src/main/java/net/minecraft/server/ChunkMap.java
-+++ b/src/main/java/net/minecraft/server/ChunkMap.java
-@@ -0,0 +0,0 @@ public class ChunkMap extends Long2ObjectOpenHashMap<Chunk> {
-         chunk.world.timings.syncChunkLoadPostTimer.startTiming(); // Paper
-         lastChunkByPos = chunk; // Paper
-         Chunk chunk1 = (Chunk) super.put(i, chunk);
-+        if (chunk1 == null) { // Paper - we should never be overwriting chunks
-         ChunkCoordIntPair chunkcoordintpair = new ChunkCoordIntPair(i);
- 
-         for (int j = chunkcoordintpair.x - 1; j <= chunkcoordintpair.x + 1; ++j) {
-@@ -0,0 +0,0 @@ public class ChunkMap extends Long2ObjectOpenHashMap<Chunk> {
-                     chunk.setNeighborLoaded(x, z);
-                 }
-             }
-+            // Paper start
-+        } } else {
-+            a.error("Overwrote existing chunk! (" + chunk.world.getWorld().getName() + ":" + chunk.locX+"," + chunk.locZ + ")", new IllegalStateException());
-         }
-+        // Paper end
-         // Paper start - if this is a spare chunk (not part of any players view distance), go ahead and queue it for unload.
-         if (!((WorldServer)chunk.world).getPlayerChunkMap().isChunkInUse(chunk.locX, chunk.locZ)) {
-             if (chunk.world.paperConfig.delayChunkUnloadsBy > 0) {
-@@ -0,0 +0,0 @@ public class ChunkMap extends Long2ObjectOpenHashMap<Chunk> {
- 
-     public Chunk a(long i) {
-         Chunk chunk = (Chunk) super.remove(i);
-+        if (chunk != null) { // Paper - don't decrement if we didn't remove anything
-         ChunkCoordIntPair chunkcoordintpair = new ChunkCoordIntPair(i);
- 
-         for (int j = chunkcoordintpair.x - 1; j <= chunkcoordintpair.x + 1; ++j) {
-@@ -0,0 +0,0 @@ public class ChunkMap extends Long2ObjectOpenHashMap<Chunk> {
-         }
- 
-         // Paper start
-+        } // close if (chunk != null)
-         if (lastChunkByPos != null && i == lastChunkByPos.chunkKey) {
-             lastChunkByPos = null;
-         }
---