Run thread directly

src/main/java/net/minestom/server/UpdateManager.java

@@ -120,12 +120,11 @@ public final class UpdateManager {
 
         // Server tick (instance/chunk/entity)
         // Synchronize with the update manager instance, like the signal for chunk load/unload
+        final CountDownLatch countDownLatch;
         synchronized (this) {
-            this.threadProvider.prepareUpdate(tickStart);
+            countDownLatch = threadProvider.update(tickStart);
         }
 
-        CountDownLatch countDownLatch = threadProvider.notifyThreads();
-
         // Wait tick end
         try {
             countDownLatch.await();
@@ -199,7 +198,7 @@ public final class UpdateManager {
      * <p>
      * WARNING: should be automatically done by the {@link Instance} implementation.
      *
-     * @param chunk    the loaded chunk
+     * @param chunk the loaded chunk
      */
     public synchronized void signalChunkLoad(@NotNull Chunk chunk) {
         if (this.threadProvider == null)
@@ -212,7 +211,7 @@ public final class UpdateManager {
      * <p>
      * WARNING: should be automatically done by the {@link Instance} implementation.
      *
-     * @param chunk    the unloaded chunk
+     * @param chunk the unloaded chunk
      */
     public synchronized void signalChunkUnload(@NotNull Chunk chunk) {
         if (this.threadProvider == null)

src/main/java/net/minestom/server/thread/BatchThread.java

@@ -33,10 +33,6 @@ public class BatchThread extends Thread {
         return queue;
     }
 
-    public void addRunnable(@NotNull Runnable runnable) {
-        this.runnable.queue.add(runnable);
-    }
-
     public void shutdown() {
         this.runnable.stop = true;
     }
@@ -91,8 +87,9 @@ public class BatchThread extends Thread {
             }
         }
 
-        public synchronized void startTick(@NotNull CountDownLatch countDownLatch) {
+        public synchronized void startTick(@NotNull CountDownLatch countDownLatch, Runnable runnable) {
             synchronized (tickLock) {
+                this.queue.add(runnable);
                 this.countDownLatch = countDownLatch;
                 this.tickLock.notifyAll();
             }

src/main/java/net/minestom/server/thread/ThreadProvider.java

@@ -86,10 +86,22 @@ public abstract class ThreadProvider {
      *
      * @param time the tick time in milliseconds
      */
-    public void prepareUpdate(long time) {
-        this.threadChunkMap.forEach((threadId, chunkEntries) -> {
-            BatchThread thread = threads.get(threadId);
+    public @NotNull CountDownLatch update(long time) {
+        CountDownLatch countDownLatch = new CountDownLatch(threads.size());
+        for (BatchThread thread : threads) {
+            final int id = threads.indexOf(thread);
+            if (id == -1) {
+                countDownLatch.countDown();
+                continue;
+            }
 
+            final var chunkEntries = threadChunkMap.get(id);
+            if (chunkEntries == null) {
+                countDownLatch.countDown();
+                continue;
+            }
+
+            // Cache chunk entities
             Map<Chunk, List<Entity>> chunkListMap = new HashMap<>(chunkEntries.size());
             for (ChunkEntry chunkEntry : chunkEntries) {
                 var chunk = chunkEntry.chunk;
@@ -97,7 +109,8 @@ public abstract class ThreadProvider {
                 chunkListMap.put(chunk, entities);
             }
 
-            thread.addRunnable(() -> {
+            // Execute tick
+            thread.getMainRunnable().startTick(countDownLatch, () -> {
                 chunkListMap.forEach((chunk, entities) -> {
                     chunk.tick(time);
                     entities.forEach(entity -> {
@@ -105,19 +118,11 @@ public abstract class ThreadProvider {
                     });
                 });
             });
-        });
-    }
-
-    @NotNull
-    public CountDownLatch notifyThreads() {
-        CountDownLatch countDownLatch = new CountDownLatch(threads.size());
-        for (BatchThread thread : threads) {
-            final BatchThread.BatchRunnable runnable = thread.getMainRunnable();
-            runnable.startTick(countDownLatch);
         }
         return countDownLatch;
     }
 
+
     public void shutdown() {
         this.threads.forEach(BatchThread::shutdown);
     }