From e4331844ace9e7b9ed8281239e1c9e97a203fa81 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Aur=C3=A9lien?=
 <43724816+Aurelien30000@users.noreply.github.com>
Date: Tue, 13 Apr 2021 16:55:12 +0200
Subject: [PATCH] Fix performance issues getting next file ids (#1027)

* Greetly optimize disk history

* Greetly optimize disk cfi changeset

* Remove wildcard import.

* Improve performance fix

* Improved performance fix
---
 .../boydti/fawe/object/changeset/CFIChangeSet.java  | 13 +++++++++++--
 .../fawe/object/changeset/DiskStorageHistory.java   | 11 +++++++++--
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/worldedit-core/src/main/java/com/boydti/fawe/object/changeset/CFIChangeSet.java b/worldedit-core/src/main/java/com/boydti/fawe/object/changeset/CFIChangeSet.java
index 83bcee1ce..7fe5c9f3a 100644
--- a/worldedit-core/src/main/java/com/boydti/fawe/object/changeset/CFIChangeSet.java
+++ b/worldedit-core/src/main/java/com/boydti/fawe/object/changeset/CFIChangeSet.java
@@ -12,17 +12,26 @@ import com.sk89q.worldedit.world.biome.BiomeType;
 import java.io.File;
 import java.io.IOException;
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.Iterator;
+import java.util.Map;
 import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
 
 public class CFIChangeSet extends AbstractChangeSet {
 
+    private static final Map<UUID, Map<String, Integer>> NEXT_INDEX = new ConcurrentHashMap<>();
+
     private final File file;
 
     public CFIChangeSet(HeightMapMCAGenerator hmmg, UUID uuid) throws IOException {
         super(hmmg);
-        File folder = MainUtil.getFile(Fawe.imp().getDirectory(), Settings.IMP.PATHS.HISTORY + File.separator + uuid + File.separator + "CFI" + File.separator + hmmg.getId());
-        int max = MainUtil.getMaxFileId(folder);
+        final String hmmgId = hmmg.getId();
+        final File folder = MainUtil.getFile(Fawe.imp().getDirectory(), Settings.IMP.PATHS.HISTORY + File.separator + uuid + File.separator + "CFI" + File.separator + hmmgId);
+
+        final int max = NEXT_INDEX.computeIfAbsent(uuid, _uuid -> new HashMap<>())
+                .compute(hmmgId, (_hmmgId, id) -> (id == null ? MainUtil.getMaxFileId(folder) : id) + 1) - 1;
+
         this.file = new File(folder, max + ".cfi");
         File parent = this.file.getParentFile();
         if (!parent.exists()) {
diff --git a/worldedit-core/src/main/java/com/boydti/fawe/object/changeset/DiskStorageHistory.java b/worldedit-core/src/main/java/com/boydti/fawe/object/changeset/DiskStorageHistory.java
index 296887527..7e4b9078e 100644
--- a/worldedit-core/src/main/java/com/boydti/fawe/object/changeset/DiskStorageHistory.java
+++ b/worldedit-core/src/main/java/com/boydti/fawe/object/changeset/DiskStorageHistory.java
@@ -19,7 +19,9 @@ import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.util.Map;
 import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
 
 /**
  * Store the change on disk
@@ -30,6 +32,8 @@ import java.util.UUID;
  */
 public class DiskStorageHistory extends FaweStreamChangeSet {
 
+    private static final Map<String, Map<UUID, Integer>> NEXT_INDEX = new ConcurrentHashMap<>();
+
     private UUID uuid;
     private File bdFile;
     private File bioFile;
@@ -67,8 +71,11 @@ public class DiskStorageHistory extends FaweStreamChangeSet {
     }
 
     private void init(UUID uuid, String worldName) {
-        File folder = MainUtil.getFile(Fawe.imp().getDirectory(), Settings.IMP.PATHS.HISTORY + File.separator + worldName + File.separator + uuid);
-        int max = MainUtil.getMaxFileId(folder);
+        final File folder = MainUtil.getFile(Fawe.imp().getDirectory(), Settings.IMP.PATHS.HISTORY + File.separator + worldName + File.separator + uuid);
+
+        final int max = NEXT_INDEX.computeIfAbsent(worldName, _worldName -> new ConcurrentHashMap<>())
+                .compute(uuid, (_uuid, id) -> (id == null ? MainUtil.getMaxFileId(folder) : id) + 1) - 1;
+
         init(uuid, max);
     }