From 6604a1f3bd3e6dd37e050df1937e1f75b2eb9d38 Mon Sep 17 00:00:00 2001
From: Colin McDonald <cmcdonald.main@gmail.com>
Date: Wed, 26 Apr 2017 23:23:20 -0400
Subject: [PATCH] Improve 1.8 compression performance


diff --git a/src/main/java/net/frozenorb/ReusableByteArray.java b/src/main/java/net/frozenorb/ReusableByteArray.java
new file mode 100644
index 000000000..7616f7266
--- /dev/null
+++ b/src/main/java/net/frozenorb/ReusableByteArray.java
@@ -0,0 +1,29 @@
+package net.frozenorb;
+
+public class ReusableByteArray {
+
+    private final ThreadLocal<byte[]> arrays;
+
+    public ReusableByteArray(final int initialSize) {
+        arrays = new ThreadLocal<byte[]>() {
+            @Override
+            protected byte[] initialValue() {
+                return new byte[initialSize];
+            }
+        };
+    }
+
+    /**
+     * Returns a (thread local) byte array of at least minSize
+     * @param minSize Minimum size of returned array
+     * @return byte array
+     */
+    public byte[] get(int minSize) {
+        byte[] array = arrays.get();
+        if (array.length < minSize) {
+            array = new byte[minSize];
+            arrays.set(array);
+        }
+        return array;
+    }
+}
diff --git a/src/main/java/org/spigotmc/SpigotCompressor.java b/src/main/java/org/spigotmc/SpigotCompressor.java
index 2e0857ea0..431c9ae82 100644
--- a/src/main/java/org/spigotmc/SpigotCompressor.java
+++ b/src/main/java/org/spigotmc/SpigotCompressor.java
@@ -1,5 +1,6 @@
 package org.spigotmc;
 
+import net.frozenorb.ReusableByteArray;
 import net.minecraft.server.PacketDataSerializer;
 import net.minecraft.util.io.netty.buffer.ByteBuf;
 import net.minecraft.util.io.netty.channel.ChannelHandlerContext;
@@ -12,32 +13,42 @@ public class SpigotCompressor extends MessageToByteEncoder
 
     private final byte[] buffer = new byte[8192];
     private final Deflater deflater = new Deflater();
+    private static final ReusableByteArray reusableData = new ReusableByteArray(0x70000); // rough size estimate from a quick play test
 
     @Override
     protected void encode(ChannelHandlerContext ctx, Object msg, ByteBuf out) throws Exception
     {
         ByteBuf in = (ByteBuf) msg;
         int origSize = in.readableBytes();
-        PacketDataSerializer serializer = new PacketDataSerializer( out );
 
         if ( origSize < 256 )
         {
-            serializer.b( 0 );
-            serializer.writeBytes( in );
+            writeVarInt( 0, out );
+            out.writeBytes( in );
         } else
         {
-            byte[] data = new byte[ origSize ];
-            in.readBytes( data );
+            byte[] data = reusableData.get(origSize);
+            in.readBytes( data, 0, origSize );
 
-            serializer.b( data.length );
+            writeVarInt( origSize, out );
 
-            deflater.setInput( data );
+            deflater.setInput( data, 0, origSize );
             deflater.finish();
             while (!deflater.finished()) {
                 int count = deflater.deflate( buffer );
-                serializer.writeBytes( buffer, 0, count );
+                out.writeBytes( buffer, 0, count );
             }
             deflater.reset();
         }
     }
+
+    public static void writeVarInt(int val, ByteBuf out) {
+        while ((val & -128) != 0) {
+            out.writeByte(val & 127 | 128);
+            val >>>= 7;
+        }
+
+        out.writeByte(val);
+    }
+
 }
diff --git a/src/main/java/org/spigotmc/SpigotDecompressor.java b/src/main/java/org/spigotmc/SpigotDecompressor.java
index ffebf5db1..7f4eebaa3 100644
--- a/src/main/java/org/spigotmc/SpigotDecompressor.java
+++ b/src/main/java/org/spigotmc/SpigotDecompressor.java
@@ -1,5 +1,6 @@
 package org.spigotmc;
 
+import net.frozenorb.ReusableByteArray;
 import net.minecraft.server.PacketDataSerializer;
 import net.minecraft.util.io.netty.buffer.ByteBuf;
 import net.minecraft.util.io.netty.buffer.Unpooled;
@@ -13,6 +14,7 @@ public class SpigotDecompressor extends ByteToMessageDecoder
 {
 
     private final Inflater inflater = new Inflater();
+    private static final ReusableByteArray reusableCompressedData = new ReusableByteArray(8192);
 
     @Override
     protected void decode(ChannelHandlerContext channelHandlerContext, ByteBuf byteBuf, List<Object> objects) throws Exception
@@ -29,9 +31,10 @@ public class SpigotDecompressor extends ByteToMessageDecoder
             objects.add( serializer.readBytes( serializer.readableBytes() ) );
         } else
         {
-            byte[] compressedData = new byte[ serializer.readableBytes() ];
-            serializer.readBytes( compressedData );
-            inflater.setInput( compressedData );
+            int compressedSize = serializer.readableBytes();
+            byte[] compressedData = reusableCompressedData.get(compressedSize);
+            serializer.readBytes( compressedData, 0, compressedSize );
+            inflater.setInput( compressedData, 0, compressedSize );
 
             byte[] data = new byte[ size ];
             inflater.inflate( data );
-- 
2.13.3