PaperMC/patches/server/1032-Separate-dimensiondata-executor.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Nassim Jahnke <nassim@njahnke.dev>
Date: Thu, 28 Nov 2024 10:35:58 +0100
Subject: [PATCH] Separate dimensiondata executor


diff --git a/src/main/java/net/minecraft/Util.java b/src/main/java/net/minecraft/Util.java
index 1a31024b46a5d7960f1e0f172f8ebcf396dd3139..38ffa1c4c204f73746c4b87127de92b631548eb1 100644
--- a/src/main/java/net/minecraft/Util.java
+++ b/src/main/java/net/minecraft/Util.java
@@ -94,6 +94,7 @@ public class Util {
     private static final String MAX_THREADS_SYSTEM_PROPERTY = "max.bg.threads";
     private static final TracingExecutor BACKGROUND_EXECUTOR = makeExecutor("Main", -1); // Paper - Perf: add priority
     private static final TracingExecutor IO_POOL = makeIoExecutor("IO-Worker-", false);
+    public static final TracingExecutor DIMENSION_DATA_IO_POOL = makeExtraIoExecutor("Dimension-Data-IO-Worker-"); // Paper - Separate dimension data IO pool
     private static final TracingExecutor DOWNLOAD_POOL = makeIoExecutor("Download-", true);
     // Paper start - don't submit BLOCKING PROFILE LOOKUPS to the world gen thread
     public static final ExecutorService PROFILE_EXECUTOR = Executors.newFixedThreadPool(2, new java.util.concurrent.ThreadFactory() {
@@ -265,6 +266,21 @@ public class Util {
         }));
     }
 
+    // Paper start - Separate dimension data IO pool
+    private static TracingExecutor makeExtraIoExecutor(String namePrefix) {
+        AtomicInteger atomicInteger = new AtomicInteger(1);
+        return new TracingExecutor(Executors.newFixedThreadPool(4, runnable -> {
+            Thread thread = new Thread(runnable);
+            String string2 = namePrefix + atomicInteger.getAndIncrement();
+            TracyClient.setThreadName(string2, namePrefix.hashCode());
+            thread.setName(string2);
+            thread.setDaemon(false);
+            thread.setUncaughtExceptionHandler(Util::onThreadException);
+            return thread;
+        }));
+    }
+    // Paper end - Separate dimension data IO pool
+
     public static void throwAsRuntime(Throwable t) {
         throw t instanceof RuntimeException ? (RuntimeException)t : new RuntimeException(t);
     }
diff --git a/src/main/java/net/minecraft/world/level/storage/DimensionDataStorage.java b/src/main/java/net/minecraft/world/level/storage/DimensionDataStorage.java
index 3c3b18e5b419a0f785467c511dcdd65873ad0989..9272c91e0ee489091fdf1fedcf3801c070e9e82a 100644
--- a/src/main/java/net/minecraft/world/level/storage/DimensionDataStorage.java
+++ b/src/main/java/net/minecraft/world/level/storage/DimensionDataStorage.java
@@ -139,7 +139,7 @@ public class DimensionDataStorage implements AutoCloseable {
         } else {
             int i = Util.maxAllowedExecutorThreads();
             int j = map.size();
-            if (j > i) {
+            if (false && j > i) { // Paper - Separate dimension data IO pool; just throw them into the fixed pool queue
                 this.pendingWriteFuture = this.pendingWriteFuture.thenCompose(object -> {
                     List<CompletableFuture<?>> list = new ArrayList<>(i);
                     int k = Mth.positiveCeilDiv(j, i);
@@ -160,7 +160,7 @@ public class DimensionDataStorage implements AutoCloseable {
                         v -> CompletableFuture.allOf(
                                 map.entrySet()
                                     .stream()
-                                    .map(entry -> CompletableFuture.runAsync(() -> tryWrite(entry.getKey(), entry.getValue()), Util.ioPool()))
+                                    .map(entry -> CompletableFuture.runAsync(() -> tryWrite(entry.getKey(), entry.getValue()), Util.DIMENSION_DATA_IO_POOL)) // Paper - Separate dimension data IO pool
                                     .toArray(CompletableFuture[]::new)
                             )
                     );