Improving chunk generation performance

src/main/java/net/minestom/server/extras/mojangAuth/CipherBase.java

@@ -2,51 +2,53 @@ package net.minestom.server.extras.mojangAuth;
 
 import io.netty.buffer.ByteBuf;
 import io.netty.channel.ChannelHandlerContext;
+import org.jetbrains.annotations.NotNull;
 
 import javax.crypto.Cipher;
 import javax.crypto.ShortBufferException;
 
 public class CipherBase {
-   private final Cipher cipher;
-   private byte[] inTempArray = new byte[0];
-   private byte[] outTempArray = new byte[0];
 
-   protected CipherBase(Cipher cipher) {
-      this.cipher = cipher;
-   }
+    private final Cipher cipher;
+    private byte[] inTempArray = new byte[0];
+    private byte[] outTempArray = new byte[0];
 
-   private byte[] bufToByte(ByteBuf buffer) {
-      int remainingBytes = buffer.readableBytes();
+    protected CipherBase(@NotNull Cipher cipher) {
+        this.cipher = cipher;
+    }
 
-      // Need to resize temp array
-      if (inTempArray.length < remainingBytes) {
-         inTempArray = new byte[remainingBytes];
-      }
+    private byte[] bufToByte(ByteBuf buffer) {
+        int remainingBytes = buffer.readableBytes();
 
-      buffer.readBytes(inTempArray, 0, remainingBytes);
-      return inTempArray;
-   }
+        // Need to resize temp array
+        if (inTempArray.length < remainingBytes) {
+            inTempArray = new byte[remainingBytes];
+        }
 
-   protected ByteBuf decrypt(ChannelHandlerContext channelHandlerContext, ByteBuf byteBufIn) throws ShortBufferException {
-      int remainingBytes = byteBufIn.readableBytes();
-      byte[] bytes = bufToByte(byteBufIn);
+        buffer.readBytes(inTempArray, 0, remainingBytes);
+        return inTempArray;
+    }
 
-      ByteBuf outputBuffer = channelHandlerContext.alloc().heapBuffer(cipher.getOutputSize(remainingBytes));
-      outputBuffer.writerIndex(cipher.update(bytes, 0, remainingBytes, outputBuffer.array(), outputBuffer.arrayOffset()));
+    protected ByteBuf decrypt(ChannelHandlerContext channelHandlerContext, ByteBuf byteBufIn) throws ShortBufferException {
+        int remainingBytes = byteBufIn.readableBytes();
+        byte[] bytes = bufToByte(byteBufIn);
 
-      return outputBuffer;
-   }
+        ByteBuf outputBuffer = channelHandlerContext.alloc().heapBuffer(cipher.getOutputSize(remainingBytes));
+        outputBuffer.writerIndex(cipher.update(bytes, 0, remainingBytes, outputBuffer.array(), outputBuffer.arrayOffset()));
 
-   protected void encrypt(ByteBuf byteBufIn, ByteBuf byteBufOut) throws ShortBufferException {
-      int remainingBytes = byteBufIn.readableBytes();
-      byte[] bytes = bufToByte(byteBufIn);
-      int newSize = cipher.getOutputSize(remainingBytes);
+        return outputBuffer;
+    }
 
-      // Need to resize temp array
-      if (outTempArray.length < newSize) {
-         outTempArray = new byte[newSize];
-      }
+    protected void encrypt(ByteBuf byteBufIn, ByteBuf byteBufOut) throws ShortBufferException {
+        int remainingBytes = byteBufIn.readableBytes();
+        byte[] bytes = bufToByte(byteBufIn);
+        int newSize = cipher.getOutputSize(remainingBytes);
 
-      byteBufOut.writeBytes(outTempArray, 0, cipher.update(bytes, 0, remainingBytes, outTempArray));
-   }
+        // Need to resize temp array
+        if (outTempArray.length < newSize) {
+            outTempArray = new byte[newSize];
+        }
+
+        byteBufOut.writeBytes(outTempArray, 0, cipher.update(bytes, 0, remainingBytes, outTempArray));
+    }
 }

src/main/java/net/minestom/server/extras/mojangAuth/Decrypter.java

@@ -8,13 +8,13 @@ import javax.crypto.Cipher;
 import java.util.List;
 
 public class Decrypter extends MessageToMessageDecoder<ByteBuf> {
-   private final CipherBase cipher;
+    private final CipherBase cipher;
 
-   public Decrypter(Cipher cipher) {
-      this.cipher = new CipherBase(cipher);
-   }
+    public Decrypter(Cipher cipher) {
+        this.cipher = new CipherBase(cipher);
+    }
 
-   protected void decode(ChannelHandlerContext channelHandlerContext, ByteBuf byteBuf, List<Object> list) throws Exception {
-      list.add(this.cipher.decrypt(channelHandlerContext, byteBuf));
-   }
+    protected void decode(ChannelHandlerContext channelHandlerContext, ByteBuf byteBuf, List<Object> list) throws Exception {
+        list.add(this.cipher.decrypt(channelHandlerContext, byteBuf));
+    }
 }

src/main/java/net/minestom/server/instance/InstanceContainer.java

@@ -503,7 +503,7 @@ public class InstanceContainer extends Instance {
     @Override
     public ChunkBatch createChunkBatch(@NotNull Chunk chunk) {
         Check.notNull(chunk, "The chunk of a ChunkBatch cannot be null");
-        return new ChunkBatch(this, chunk);
+        return new ChunkBatch(this, chunk, false);
     }
 
     @Override
@@ -540,7 +540,7 @@ public class InstanceContainer extends Instance {
 
         if (chunkGenerator != null && chunk.shouldGenerate()) {
             // Execute the chunk generator to populate the chunk
-            final ChunkBatch chunkBatch = createChunkBatch(chunk);
+            final ChunkBatch chunkBatch = new ChunkBatch(this, chunk, true);
 
             chunkBatch.flushChunkGenerator(chunkGenerator, callback);
         } else {

src/main/java/net/minestom/server/instance/batch/ChunkBatch.java

@@ -31,6 +31,8 @@ public class ChunkBatch implements InstanceBatch {
     private final InstanceContainer instance;
     private final Chunk chunk;
 
+    private final boolean generationBatch;
+
     // Need to be synchronized manually
     // Format: blockIndex/blockStateId/customBlockId (32/16/16 bits)
     private final LongList blocks = new LongArrayList();
@@ -39,9 +41,11 @@ public class ChunkBatch implements InstanceBatch {
     // block index - data
     private final Int2ObjectMap<Data> blockDataMap = new Int2ObjectOpenHashMap<>();
 
-    public ChunkBatch(@NotNull InstanceContainer instance, @NotNull Chunk chunk) {
+    public ChunkBatch(@NotNull InstanceContainer instance, @NotNull Chunk chunk,
+                      boolean generationBatch) {
         this.instance = instance;
         this.chunk = chunk;
+        this.generationBatch = generationBatch;
     }
 
     @Override
@@ -62,21 +66,39 @@ public class ChunkBatch implements InstanceBatch {
     }
 
     private void addBlockData(byte x, int y, byte z, short blockStateId, short customBlockId, @Nullable Data data) {
-        final int index = ChunkUtils.getBlockIndex(x, y, z);
 
-        if (data != null) {
-            synchronized (blockDataMap) {
-                this.blockDataMap.put(index, data);
+        if (isGenerationBatch()) {
+            chunk.UNSAFE_setBlock(x, y, z, blockStateId, customBlockId, data, CustomBlockUtils.hasUpdate(customBlockId));
+        } else {
+            final int index = ChunkUtils.getBlockIndex(x, y, z);
+
+            if (data != null) {
+                synchronized (blockDataMap) {
+                    this.blockDataMap.put(index, data);
+                }
+            }
+
+            long value = index;
+            value = (value << 16) | blockStateId;
+            value = (value << 16) | customBlockId;
+
+            synchronized (blocks) {
+                this.blocks.add(value);
             }
         }
+    }
 
-        long value = index;
-        value = (value << 16) | blockStateId;
-        value = (value << 16) | customBlockId;
-
-        synchronized (blocks) {
-            this.blocks.add(value);
-        }
+    /**
+     * Gets if this chunk batch is part of a chunk generation.
+     * <p>
+     * Being a generation batch mean that blocks set are not being stored
+     * but are immediately placed on the chunks. Using less memory
+     * and CPU cycles.
+     *
+     * @return true if this batch is part of a chunk generation
+     */
+    public boolean isGenerationBatch() {
+        return generationBatch;
     }
 
     /**
@@ -92,24 +114,15 @@ public class ChunkBatch implements InstanceBatch {
 
             chunkGenerator.generateChunkData(this, chunk.getChunkX(), chunk.getChunkZ());
 
-            // Check if there is anything to process
-            if (blocks.isEmpty() && !hasPopulator) {
-                OptionalCallback.execute(callback, chunk);
-                return;
-            }
-
-            singleThreadFlush(hasPopulator ? null : callback, true);
-
-            clearData(); // So the populators won't place those blocks again
-
             if (hasPopulator) {
                 for (ChunkPopulator chunkPopulator : populators) {
                     chunkPopulator.populateChunk(this, chunk);
                 }
-                singleThreadFlush(callback, true);
-
-                clearData(); // Clear populators blocks
             }
+
+            instance.scheduleNextTick(inst -> {
+                OptionalCallback.execute(callback, chunk);
+            });
         });
     }
 

src/test/java/demo/Main.java

@@ -54,7 +54,7 @@ public class Main {
         //VelocityProxy.enable("rBeJJ79W4MVU");
         //BungeeCordProxy.enable();
 
-        // MojangAuth.init();
+        //MojangAuth.init();
 
         minecraftServer.start("0.0.0.0", 25565, PlayerInit.getResponseDataConsumer());
     }

src/test/java/demo/PlayerInit.java

@@ -30,7 +30,6 @@ import net.minestom.server.utils.time.TimeUnit;
 import net.minestom.server.world.DimensionType;
 
 import java.util.UUID;
-import java.util.concurrent.ThreadLocalRandom;
 
 public class PlayerInit {
 
@@ -44,7 +43,7 @@ public class PlayerInit {
         NoiseTestGenerator noiseTestGenerator = new NoiseTestGenerator();
         instanceContainer = MinecraftServer.getInstanceManager().createInstanceContainer(DimensionType.OVERWORLD);
         instanceContainer.enableAutoChunkLoad(true);
-        instanceContainer.setChunkGenerator(chunkGeneratorDemo);
+        instanceContainer.setChunkGenerator(noiseTestGenerator);
 
         // Load some chunks beforehand
         final int loopStart = -3;
@@ -163,8 +162,8 @@ public class PlayerInit {
             player.addEventCallback(PlayerLoginEvent.class, event -> {
 
                 event.setSpawningInstance(instanceContainer);
-                int x = ThreadLocalRandom.current().nextInt()%10000;
-                player.setRespawnPoint(new Position(x, 64f, 0));
+                //int x = ThreadLocalRandom.current().nextInt()%10000;
+                player.setRespawnPoint(new Position(0, 64f, 0));
 
                 /*player.getInventory().addInventoryCondition((p, slot, clickType, inventoryConditionResult) -> {
                     if (slot == -999)