Paper/patches/server/0272-Improve-Server-Thread-Pool-and-Thread-Priorities.patch

106 lines
5.3 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Tue, 23 Oct 2018 23:14:38 -0400
Subject: [PATCH] Improve Server Thread Pool and Thread Priorities
Use a simple executor since Fork join is a much more complex pool
type and we are not using its capabilities.
Set thread priorities so main thread has above normal priority over
server threads
Allow usage of a single thread executor by not using ForkJoin so single core CPU's
and reduce worldgen thread worker count for low core count CPUs.
== AT ==
public net.minecraft.Util onThreadException(Ljava/lang/Thread;Ljava/lang/Throwable;)V
Co-authored-by: Spottedleaf <Spottedleaf@users.noreply.github.com>
diff --git a/src/main/java/io/papermc/paper/util/ServerWorkerThread.java b/src/main/java/io/papermc/paper/util/ServerWorkerThread.java
new file mode 100644
index 0000000000000000000000000000000000000000..b60f59cf5cc8eb84a6055b7861857dece7f2501b
--- /dev/null
+++ b/src/main/java/io/papermc/paper/util/ServerWorkerThread.java
@@ -0,0 +1,14 @@
+package io.papermc.paper.util;
+
+import java.util.concurrent.atomic.AtomicInteger;
+import net.minecraft.Util;
+
+public class ServerWorkerThread extends Thread {
+ private static final AtomicInteger threadId = new AtomicInteger(1);
+ public ServerWorkerThread(Runnable target, String poolName, int prioritityModifier) {
+ super(target, "Worker-" + poolName + "-" + threadId.getAndIncrement());
+ setPriority(Thread.NORM_PRIORITY+prioritityModifier); // Deprioritize over main
+ this.setDaemon(true);
+ this.setUncaughtExceptionHandler(Util::onThreadException);
+ }
+}
diff --git a/src/main/java/net/minecraft/Util.java b/src/main/java/net/minecraft/Util.java
index aa52b271bd556a29f774fde375b713d0d187521b..90f5e7d36719dc9b464dd6ba0335da035bab29d3 100644
--- a/src/main/java/net/minecraft/Util.java
+++ b/src/main/java/net/minecraft/Util.java
@@ -86,7 +86,7 @@ public class Util {
private static final int DEFAULT_MAX_THREADS = 255;
private static final int DEFAULT_SAFE_FILE_OPERATION_RETRIES = 10;
private static final String MAX_THREADS_SYSTEM_PROPERTY = "max.bg.threads";
- private static final ExecutorService BACKGROUND_EXECUTOR = makeExecutor("Main");
+ private static final ExecutorService BACKGROUND_EXECUTOR = makeExecutor("Main", -1); // Paper - add -1 priority
private static final ExecutorService IO_POOL = makeIoExecutor("IO-Worker-", false);
private static final ExecutorService DOWNLOAD_POOL = makeIoExecutor("Download-", true);
// Paper start - don't submit BLOCKING PROFILE LOOKUPS to the world gen thread
@@ -152,15 +152,27 @@ public class Util {
return FILENAME_DATE_TIME_FORMATTER.format(ZonedDateTime.now());
}
- private static ExecutorService makeExecutor(String name) {
- int i = Mth.clamp(Runtime.getRuntime().availableProcessors() - 1, 1, getMaxThreads());
+ private static ExecutorService makeExecutor(String s, int priorityModifier) { // Paper - add priority
+ // Paper start - use simpler thread pool that allows 1 thread and reduce worldgen thread worker count for low core count CPUs
+ int cpus = Runtime.getRuntime().availableProcessors() / 2;
+ int i;
+ if (cpus <= 4) {
+ i = cpus <= 2 ? 1 : 2;
+ } else if (cpus <= 8) {
+ // [5, 8]
+ i = Math.max(3, cpus - 2);
+ } else {
+ i = cpus * 2 / 3;
+ }
+ i = Math.min(8, i);
+ i = Integer.getInteger("Paper.WorkerThreadCount", i);
ExecutorService executorService;
if (i <= 0) {
executorService = MoreExecutors.newDirectExecutorService();
} else {
- AtomicInteger atomicInteger = new AtomicInteger(1);
- executorService = new ForkJoinPool(i, (pool) -> {
- ForkJoinWorkerThread forkJoinWorkerThread = new ForkJoinWorkerThread(pool) {
+ executorService = new java.util.concurrent.ThreadPoolExecutor(i, i,0L, TimeUnit.MILLISECONDS, new java.util.concurrent.LinkedBlockingQueue<>(), target -> new io.papermc.paper.util.ServerWorkerThread(target, s, priorityModifier));
+ }
+ /*
@Override
protected void onTermination(Throwable throwable) {
if (throwable != null) {
@@ -176,6 +188,7 @@ public class Util {
return forkJoinWorkerThread;
}, Util::onThreadException, true);
}
+ }*/ // Paper end
return executorService;
}
diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 79a7f64edcfc750bf2753b5b20e4c2ae322e01ab..7a12c0f5a6cb205e8ae7667b9334efe1999e2a6a 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -312,6 +312,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
thread.setUncaughtExceptionHandler((thread1, throwable) -> {
MinecraftServer.LOGGER.error("Uncaught exception in server thread", throwable);
});
+ thread.setPriority(Thread.NORM_PRIORITY+2); // Paper - boost priority
if (Runtime.getRuntime().availableProcessors() > 4) {
thread.setPriority(8);
}