From c56be574082969f54bed8a2553ebb2ff7d5ce052 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Thu, 31 Mar 2016 19:17:58 -0400
Subject: [PATCH] Do not load chunks for light checks

Should only happen for blocks on the edge that uses neighbors light level
(certain blocks). In that case, there will be 3-4 other neighbors to get a light level from.

diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index d5ba601..ea187f9 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -717,6 +717,7 @@ public abstract class World implements IBlockAccess {
                 if (blockposition.getY() >= 256) {
                     blockposition = new BlockPosition(blockposition.getX(), 255, blockposition.getZ());
                 }
+                if (!this.isLoaded(blockposition)) return 0; // Paper
 
                 Chunk chunk = this.getChunkAtWorldCoords(blockposition);
 
-- 
2.8.0