From 5b3af4c629f59e7cec7df614b140c16c3454564c Mon Sep 17 00:00:00 2001
From: md_5 <git@md-5.net>
Date: Fri, 13 Dec 2013 11:58:58 +1100
Subject: [PATCH] Configurable Amount of Netty Threads

This brings back the option that the Spigot version of netty saw. By default Netty will try and use cores*2 threads, however if running multiple servers on the same machine, this can be too many threads. Additionally some people have 16 core servers. If 32 Netty threads are allowed in this setup, then the lock contention, and thus blocking between threads becomes much greater, leading to decreased performance.

diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 1bf5fa342..ad94e8adf 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -190,7 +190,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
         this.minecraftSessionService = minecraftsessionservice;
         this.gameProfileRepository = gameprofilerepository;
         this.userCache = usercache;
-        this.serverConnection = new ServerConnection(this);
+        // this.serverConnection = new ServerConnection(this); // Spigot
         this.worldLoadListenerFactory = worldloadlistenerfactory;
         this.convertable = convertable_conversionsession;
         this.worldNBTStorage = convertable_conversionsession.b();
@@ -1395,7 +1395,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
 
     @Nullable
     public ServerConnection getServerConnection() {
-        return this.serverConnection;
+        return this.serverConnection == null ? this.serverConnection = new ServerConnection(this) : this.serverConnection; // Spigot
     }
 
     public boolean ag() {
diff --git a/src/main/java/org/spigotmc/SpigotConfig.java b/src/main/java/org/spigotmc/SpigotConfig.java
index 642f3a39a..a7bf7f860 100644
--- a/src/main/java/org/spigotmc/SpigotConfig.java
+++ b/src/main/java/org/spigotmc/SpigotConfig.java
@@ -224,4 +224,11 @@ public class SpigotConfig
         }
         bungee = getBoolean( "settings.bungeecord", false );
     }
+
+    private static void nettyThreads()
+    {
+        int count = getInt( "settings.netty-threads", 4 );
+        System.setProperty( "io.netty.eventLoopThreads", Integer.toString( count ) );
+        Bukkit.getLogger().log( Level.INFO, "Using {0} threads for Netty based IO", count );
+    }
 }
-- 
2.25.1