From b32630a53238ec990917332b269e5e15d870be5a Mon Sep 17 00:00:00 2001
From: Antony Riley <antony@cyberiantiger.org>
Date: Tue, 29 Mar 2016 08:22:55 +0300
Subject: [PATCH] Sanitise RegionFileCache and make configurable.

RegionFileCache prior to this patch would close every single open region
file upon reaching a size of 256.
This patch modifies that behaviour so it closes the the least recently
used RegionFile.
The implementation uses a LinkedHashMap as an LRU cache (modified from HashMap).
The maximum size of the RegionFileCache is also made configurable.

diff --git a/src/main/java/com/destroystokyo/paper/PaperConfig.java b/src/main/java/com/destroystokyo/paper/PaperConfig.java
index 6cc99ffe43..0cef1853f5 100644
--- a/src/main/java/com/destroystokyo/paper/PaperConfig.java
+++ b/src/main/java/com/destroystokyo/paper/PaperConfig.java
@@ -218,4 +218,9 @@ public class PaperConfig {
     private static void loadPermsBeforePlugins() {
         loadPermsBeforePlugins = getBoolean("settings.load-permissions-yml-before-plugins", true);
     }
+
+    public static int regionFileCacheSize = 256;
+    private static void regionFileCacheSize() {
+        regionFileCacheSize = Math.max(getInt("settings.region-file-cache-size", 256), 4);
+    }
 }
diff --git a/src/main/java/net/minecraft/server/RegionFileCache.java b/src/main/java/net/minecraft/server/RegionFileCache.java
index 1ea9e5bb43..21b3b06f53 100644
--- a/src/main/java/net/minecraft/server/RegionFileCache.java
+++ b/src/main/java/net/minecraft/server/RegionFileCache.java
@@ -8,6 +8,7 @@ import java.io.DataOutputStream;
 import java.io.File;
 import java.io.IOException;
 import javax.annotation.Nullable;
+import com.destroystokyo.paper.PaperConfig; // Paper
 
 public abstract class RegionFileCache implements AutoCloseable {
 
@@ -25,7 +26,7 @@ public abstract class RegionFileCache implements AutoCloseable {
         if (regionfile != null) {
             return regionfile;
         } else {
-            if (this.cache.size() >= 256) {
+            if (this.cache.size() >= PaperConfig.regionFileCacheSize) { // Paper - configurable
                 ((RegionFile) this.cache.removeLast()).close();
             }
 
-- 
2.21.0