Use a Shared Random for Entities

Reduces memory usage and provides ensures more randomness, Especially since a lot of garbage entity objects get created.

Spigot-Server-Patches/0104-Use-a-Shared-Random-for-Entities.patch

@@ -0,0 +1,31 @@
+From 3e395ff227edb3569b55062d798d83d0ac448323 Mon Sep 17 00:00:00 2001
+From: Aikar <aikar@aikar.co>
+Date: Tue, 22 Mar 2016 00:33:47 -0400
+Subject: [PATCH] Use a Shared Random for Entities
+
+Reduces memory usage and provides ensures more randomness, Especially since a lot of garbage entity objects get created.
+
+diff --git a/src/main/java/net/minecraft/server/Entity.java b/src/main/java/net/minecraft/server/Entity.java
+index c28cf58..0f66b39 100644
+--- a/src/main/java/net/minecraft/server/Entity.java
++++ b/src/main/java/net/minecraft/server/Entity.java
+@@ -45,6 +45,7 @@ public abstract class Entity implements ICommandListener {
+ 
+     // CraftBukkit start
+     private static final int CURRENT_LEVEL = 2;
++    public static Random SHARED_RANDOM = new Random(); // Paper
+     static boolean isLevelAtLeast(NBTTagCompound tag, int level) {
+         return tag.hasKey("Bukkit.updateLevel") && tag.getInt("Bukkit.updateLevel") >= level;
+     }
+@@ -167,7 +168,7 @@ public abstract class Entity implements ICommandListener {
+         this.width = 0.6F;
+         this.length = 1.8F;
+         this.av = 1;
+-        this.random = new Random();
++        this.random = SHARED_RANDOM; // Paper
+         this.maxFireTicks = 1;
+         this.justCreated = true;
+         this.uniqueID = MathHelper.a(this.random);
+-- 
+2.7.4
+