More things

src/main/java/me/cortex/voxy/common/world/WorldEngine.java

@@ -41,8 +41,8 @@ public class WorldEngine {
         this.maxMipLevels = maxMipLayers;
         this.storage = storage;
         this.mapper = new Mapper(this.storage);
-        //4 cache size bits means that the section tracker has 16 separate maps that it uses
+        //5 cache size bits means that the section tracker has 32 separate maps that it uses
-        this.sectionTracker = new ActiveSectionTracker(4, storage::loadSection, cacheCount, this);
+        this.sectionTracker = new ActiveSectionTracker(5, storage::loadSection, cacheCount, this);
     }
 
     public WorldSection acquireIfExists(int lvl, int x, int y, int z) {

src/main/java/me/cortex/voxy/commonImpl/importers/WorldImporter.java

@@ -131,7 +131,9 @@ public class WorldImporter {
                 throw new RuntimeException(e);
             }
         }
-        this.threadPool.shutdown();
+        if (!this.threadPool.isFreed()) {
+            this.threadPool.shutdown();
+        }
     }
 
     private interface IImporterMethod <T> {
@@ -237,6 +239,8 @@ public class WorldImporter {
                 }
             }
             onCompletion.accept(this.totalChunks.get());
+
+            this.threadPool.shutdown();
             this.worker = null;
         });
         this.worker.setName("World importer");