Adds performance tweaking settings to config.yml

https://github.com/BentoBoxWorld/Level/issues/122

src/main/java/world/bentobox/level/calculators/CalcIslandLevel.java

@@ -1,6 +1,15 @@
 package world.bentobox.level.calculators;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Queue;
+import java.util.Set;
+import java.util.UUID;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicLong;
 
@@ -92,17 +101,15 @@ public class CalcIslandLevel {
                 total += chunksToScan.size();
             }
         }
-        queueid = Bukkit.getScheduler().scheduleSyncRepeatingTask(addon.getPlugin(), new Runnable() {
-            public void run() {
-                for (int i = 0; i < 10; i++) {
-                    if (q.size() == 0) {
-                        return;
-                    }
-                    Chunk c = q.remove();
-                    getChunk(c);
+        queueid = Bukkit.getScheduler().scheduleSyncRepeatingTask(addon.getPlugin(), () -> {
+            for (int i = 0; i < addon.getSettings().getChunks(); i++) {
+                if (q.size() == 0) {
+                    return;
                 }
+                Chunk c = q.remove();
+                getChunk(c);
             }
-        }, 1L, 1L);
+        }, addon.getSettings().getTickDelay(), addon.getSettings().getTickDelay());
         chunksToScan.forEach(c -> worlds.forEach(w -> Util.getChunkAtAsync(w, c.x, c.z).thenAccept(this::addChunkQueue)));
 
     }

src/main/java/world/bentobox/level/config/Settings.java

@@ -23,6 +23,8 @@ public class Settings {
     private int deathpenalty;
     private long levelCost;
     private int levelWait;
+    private int chunks;
+    private long taskDelay;
 
     private List<String> gameModes;
 
@@ -34,8 +36,21 @@ public class Settings {
         // GameModes
         gameModes = level.getConfig().getStringList("game-modes");
         
+        // Performance
+        setTickDelay(level.getConfig().getLong("task-delay",1));
+        if (taskDelay < 1L) {
+            level.logError("task-delay must be at least 1");
+            setTickDelay(1L);
+        }
+        setChunks(level.getConfig().getInt("chunks", 10));
+        if (chunks < 1) {
+            level.logError("chunks must be at least 1");
+            setChunks(1);
+        }
+
         setLevelWait(level.getConfig().getInt("levelwait", 60));
         if (getLevelWait() < 0) {
+            level.logError("levelwait must be at least 0");
             setLevelWait(0);
         }
         setDeathpenalty(level.getConfig().getInt("deathpenalty", 0));
@@ -228,4 +243,32 @@ public class Settings {
         return level.getConfig().getString("level-calc", "blocks / level_cost");
     }
 
+    /**
+     * @return the chunks
+     */
+    public int getChunks() {
+        return chunks;
+    }
+
+    /**
+     * @param chunks the chunks to set
+     */
+    public void setChunks(int chunks) {
+        this.chunks = chunks;
+    }
+
+    /**
+     * @return the tickDelay
+     */
+    public long getTickDelay() {
+        return taskDelay;
+    }
+
+    /**
+     * @param tickDelay the tickDelay to set
+     */
+    public void setTickDelay(long tickDelay) {
+        this.taskDelay = tickDelay;
+    }
+
 }

src/main/resources/config.yml

@@ -9,6 +9,15 @@ game-modes:
 - CaveBlock
 #- SkyGrid
 
+# Performance settings
+# Level is very processor intensive, so these settings may need to be tweaked to optimize for your server
+# Delay between each task that loads chunks for calulcating levels
+# Increasing this will slow down level calculations but reduce average load
+task-delay: 1
+
+# Number of chunks that will be processed per task
+chunks: 10
+
 # This file lists the values for various blocks that are used to calculate the
 # island level. Level = total of all blocks in island boundary / 100.
 # Players with the permission askyblock.island.multiplier.# will have their blocks