apache · xjlgod · Aug 22, 2026 · Aug 22, 2026 · Aug 22, 2026 · Aug 22, 2026
diff --git a/build/pom.xml b/build/pom.xml
@@ -83,6 +83,7 @@
         <!-- The version of spring-boot for 'spring-boot-dependencies' and 'spring-boot-maven-plugin' -->
         <spring-boot.version>2.7.18</spring-boot.version>
         <spring-framework-bom.version>5.3.39</spring-framework-bom.version>
+        <netty.version>4.2.15.Final</netty.version>
 
         <!--  server side dependency-->
         <kafka-appender.version>0.2.0-RC2</kafka-appender.version>
@@ -111,7 +112,7 @@
         <maven-checkstyle-plugin.version>3.6.0</maven-checkstyle-plugin.version>
         <spotless-maven-plugin.version>2.44.3</spotless-maven-plugin.version>
         <palantirJavaFormat.version>2.38.0</palantirJavaFormat.version>
-        <maven-enforcer-plugin.version>3.0.0-M3</maven-enforcer-plugin.version>
+        <maven-enforcer-plugin.version>3.6.3</maven-enforcer-plugin.version>
         <dependency-check-maven.version>12.1.0</dependency-check-maven.version>
         <!-- Test -->
         <maven-surefire-plugin.version>3.0.0-M5</maven-surefire-plugin.version>
@@ -357,6 +358,11 @@
                                 <requireMavenVersion>
                                     <version>[3.6.0,)</version>
                                 </requireMavenVersion>
+                                <dependencyConvergence>
+                                    <includes>
+                                        <include>io.netty:*</include>
+                                    </includes>
+                                </dependencyConvergence>
                             </rules>
                         </configuration>
                     </execution>

diff --git a/changes/en-us/2.x.md b/changes/en-us/2.x.md
@@ -41,6 +41,7 @@ Add changes here for all PR submitted to the 2.x branch.
 ### optimize:
 - [[#8054](https://github.com/apache/incubator-seata/pull/8054)] console/namingserver modules: spring-boot upgrade to 4.0.6
 - [[#8137](https://github.com/apache/incubator-seata/pull/8137)] server modules: spring-boot upgrade to 4.0.6
+- [[#8209](https://github.com/apache/incubator-seata/pull/8209)] Upgrade Netty to 4.2.15.Final and migrate the transport event loop implementation
 
 
 ### security:
@@ -70,6 +71,7 @@ Thanks to these contributors for their code commits. Please report an unintended
 - [Seol-JY](https://github.com/Seol-JY)
 - [lhozy](https://github.com/lhozy)
 - [Zhengcy05](https://github.com/Zhengcy05)
+- [xjlgod](https://github.com/xjlgod)
 - [neu-hsc](https://github.com/neu-hsc)
 - [funky-eyes](https://github.com/funky-eyes)
 - [pyshiweijia](https://github.com/pyshiweijia)

diff --git a/changes/zh-cn/2.x.md b/changes/zh-cn/2.x.md
@@ -41,6 +41,7 @@
 ### optimize:
 - [[#8054](https://github.com/apache/incubator-seata/pull/8054)] console/namingserver 模块: spring-boot 升级到 4.0.6
 - [[#8137](https://github.com/apache/incubator-seata/pull/8137)] server 模块: spring-boot 升级到 4.0.6
+- [[#8209](https://github.com/apache/incubator-seata/pull/8209)] 升级 Netty 至 4.2.15.Final，并适配传输层事件循环实现
 
 
 ### security:
@@ -71,6 +72,7 @@
 - [Seol-JY](https://github.com/Seol-JY)
 - [lhozy](https://github.com/lhozy)
 - [Zhengcy05](https://github.com/Zhengcy05)
+- [xjlgod](https://github.com/xjlgod)
 - [neu-hsc](https://github.com/neu-hsc)
 - [funky-eyes](https://github.com/funky-eyes)
 - [pyshiweijia](https://github.com/pyshiweijia)

diff --git a/config/seata-config-etcd3/src/main/java/org/apache/seata/config/etcd3/EtcdConfiguration.java b/config/seata-config-etcd3/src/main/java/org/apache/seata/config/etcd3/EtcdConfiguration.java
@@ -29,7 +29,6 @@
 import io.etcd.jetcd.op.Op;
 import io.etcd.jetcd.options.PutOption;
 import io.etcd.jetcd.watch.WatchResponse;
-import io.netty.util.internal.ConcurrentSet;
 import org.apache.seata.common.exception.ShouldNeverHappenException;
 import org.apache.seata.common.thread.NamedThreadFactory;
 import org.apache.seata.common.util.CollectionUtils;
@@ -314,7 +313,7 @@ private static void initSeataConfig() {
 
                 EtcdListener etcdListener = new EtcdListener(etcdConfigKey, null);
                 CONFIG_LISTENERS_MAP
-                        .computeIfAbsent(etcdConfigKey, key -> new ConcurrentSet<>())
+                        .computeIfAbsent(etcdConfigKey, key -> ConcurrentHashMap.newKeySet())
                         .add(etcdListener);
                 etcdListener.onProcessEvent(new ConfigurationChangeEvent());
             }

diff --git a/core/src/main/java/org/apache/seata/core/protocol/detector/HttpDetector.java b/core/src/main/java/org/apache/seata/core/protocol/detector/HttpDetector.java
@@ -56,6 +56,10 @@ public boolean detect(ByteBuf in) {
     }
 
     private boolean startsWith(ByteBuf buffer, String prefix) {
+        if (buffer.readableBytes() < prefix.length()) {
+            return false;
+        }
+
         for (int i = 0; i < prefix.length(); i++) {
             if (buffer.getByte(i) != (byte) prefix.charAt(i)) {
                 return false;

diff --git a/core/src/main/java/org/apache/seata/core/rpc/netty/NettyBaseConfig.java b/core/src/main/java/org/apache/seata/core/rpc/netty/NettyBaseConfig.java
@@ -24,7 +24,6 @@
 import io.netty.channel.socket.nio.NioServerSocketChannel;
 import io.netty.channel.socket.nio.NioSocketChannel;
 import io.netty.util.NettyRuntime;
-import io.netty.util.internal.PlatformDependent;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.seata.config.Configuration;
 import org.apache.seata.config.ConfigurationFactory;
@@ -100,7 +99,7 @@ public class NettyBaseConfig {
             WORKER_THREAD_SIZE = WorkThreadMode.Default.getValue();
         }
 
-        boolean useEpoll = !PlatformDependent.isWindows() && !PlatformDependent.isOsx() && Epoll.isAvailable();
+        boolean useEpoll = Epoll.isAvailable();
         SERVER_CHANNEL_CLAZZ = useEpoll ? EpollServerSocketChannel.class : NioServerSocketChannel.class;
         CLIENT_CHANNEL_CLAZZ = useEpoll ? EpollSocketChannel.class : NioSocketChannel.class;
 

diff --git a/core/src/main/java/org/apache/seata/core/rpc/netty/NettyClientBootstrap.java b/core/src/main/java/org/apache/seata/core/rpc/netty/NettyClientBootstrap.java
@@ -17,6 +17,7 @@
 package org.apache.seata.core.rpc.netty;
 
 import io.netty.bootstrap.Bootstrap;
+import io.netty.buffer.PooledByteBufAllocator;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelDuplexHandler;
 import io.netty.channel.ChannelFuture;
@@ -27,17 +28,17 @@
 import io.netty.channel.ChannelOption;
 import io.netty.channel.ChannelPipeline;
 import io.netty.channel.EventLoopGroup;
+import io.netty.channel.MultiThreadIoEventLoopGroup;
 import io.netty.channel.epoll.Epoll;
 import io.netty.channel.epoll.EpollChannelOption;
-import io.netty.channel.epoll.EpollEventLoopGroup;
+import io.netty.channel.epoll.EpollIoHandler;
 import io.netty.channel.epoll.EpollMode;
-import io.netty.channel.nio.NioEventLoopGroup;
+import io.netty.channel.nio.NioIoHandler;
 import io.netty.channel.socket.SocketChannel;
 import io.netty.handler.codec.http2.Http2FrameCodecBuilder;
 import io.netty.handler.codec.http2.Http2MultiplexHandler;
 import io.netty.handler.codec.http2.Http2StreamChannelBootstrap;
 import io.netty.handler.timeout.IdleStateHandler;
-import io.netty.util.internal.PlatformDependent;
 import org.apache.seata.common.exception.FrameworkException;
 import org.apache.seata.common.thread.NamedThreadFactory;
 import org.apache.seata.core.protocol.Protocol;
@@ -123,14 +124,15 @@ public void start() {
                 .option(ChannelOption.SO_KEEPALIVE, true)
                 .option(ChannelOption.CONNECT_TIMEOUT_MILLIS, nettyClientConfig.getConnectTimeoutMillis())
                 .option(ChannelOption.SO_SNDBUF, nettyClientConfig.getClientSocketSndBufSize())
-                .option(ChannelOption.SO_RCVBUF, nettyClientConfig.getClientSocketRcvBufSize());
+                .option(ChannelOption.SO_RCVBUF, nettyClientConfig.getClientSocketRcvBufSize())
+                .option(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT);
 
-        if (PlatformDependent.isWindows() || PlatformDependent.isOsx()) {
-            LOGGER.info("client run on MacOS/Windows, fallback to NIO.");
-        } else if (Epoll.isAvailable()) {
+        if (Epoll.isAvailable()) {
             bootstrap
                     .option(EpollChannelOption.EPOLL_MODE, EpollMode.EDGE_TRIGGERED)
                     .option(EpollChannelOption.TCP_QUICKACK, true);
+        } else if (LOGGER.isInfoEnabled()) {
+            LOGGER.info("Epoll is unavailable, fallback to NIO: {}", Epoll.unavailabilityCause());
         }
 
         bootstrap.handler(new ChannelInitializer<SocketChannel>() {
@@ -234,17 +236,19 @@ private EventLoopGroup getOrCreateEventLoopGroupWorker(int selectorThreadSizeThr
 
     private EventLoopGroup createEventLoopGroupWorker(int selectorThreadSizeThreadSize) {
         if (NettyServerConfig.enableEpoll()) {
-            return new EpollEventLoopGroup(
+            return new MultiThreadIoEventLoopGroup(
                     selectorThreadSizeThreadSize,
                     new NamedThreadFactory(
                             getThreadPrefix(this.nettyClientConfig.getClientSelectorThreadPrefix()),
-                            selectorThreadSizeThreadSize));
+                            selectorThreadSizeThreadSize),
+                    EpollIoHandler.newFactory());
         }
 
-        return new NioEventLoopGroup(
+        return new MultiThreadIoEventLoopGroup(
                 selectorThreadSizeThreadSize,
                 new NamedThreadFactory(
                         getThreadPrefix(this.nettyClientConfig.getClientSelectorThreadPrefix()),
-                        selectorThreadSizeThreadSize));
+                        selectorThreadSizeThreadSize),
+                NioIoHandler.newFactory());
     }
 }
diff --git a/core/src/main/java/org/apache/seata/core/rpc/netty/NettyServerBootstrap.java b/core/src/main/java/org/apache/seata/core/rpc/netty/NettyServerBootstrap.java
@@ -17,14 +17,16 @@
 package org.apache.seata.core.rpc.netty;
 
 import io.netty.bootstrap.ServerBootstrap;
+import io.netty.buffer.PooledByteBufAllocator;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelOption;
 import io.netty.channel.EventLoopGroup;
+import io.netty.channel.MultiThreadIoEventLoopGroup;
 import io.netty.channel.WriteBufferWaterMark;
-import io.netty.channel.epoll.EpollEventLoopGroup;
-import io.netty.channel.nio.NioEventLoopGroup;
+import io.netty.channel.epoll.EpollIoHandler;
+import io.netty.channel.nio.NioIoHandler;
 import io.netty.channel.socket.SocketChannel;
 import io.netty.handler.timeout.IdleStateHandler;
 import org.apache.seata.common.ConfigurationKeys;
@@ -69,27 +71,31 @@ public class NettyServerBootstrap implements RemotingBootstrap {
     public NettyServerBootstrap(NettyServerConfig nettyServerConfig) {
         this.nettyServerConfig = nettyServerConfig;
         if (NettyServerConfig.enableEpoll()) {
-            this.eventLoopGroupBoss = new EpollEventLoopGroup(
+            this.eventLoopGroupBoss = new MultiThreadIoEventLoopGroup(
                     nettyServerConfig.getBossThreadSize(),
                     new NamedThreadFactory(
-                            nettyServerConfig.getBossThreadPrefix(), nettyServerConfig.getBossThreadSize(), false));
-            this.eventLoopGroupWorker = new EpollEventLoopGroup(
+                            nettyServerConfig.getBossThreadPrefix(), nettyServerConfig.getBossThreadSize(), false),
+                    EpollIoHandler.newFactory());
+            this.eventLoopGroupWorker = new MultiThreadIoEventLoopGroup(
                     nettyServerConfig.getServerWorkerThreads(),
                     new NamedThreadFactory(
                             nettyServerConfig.getWorkerThreadPrefix(),
                             nettyServerConfig.getServerWorkerThreads(),
-                            false));
+                            false),
+                    EpollIoHandler.newFactory());
         } else {
-            this.eventLoopGroupBoss = new NioEventLoopGroup(
+            this.eventLoopGroupBoss = new MultiThreadIoEventLoopGroup(
                     nettyServerConfig.getBossThreadSize(),
                     new NamedThreadFactory(
-                            nettyServerConfig.getBossThreadPrefix(), nettyServerConfig.getBossThreadSize(), false));
-            this.eventLoopGroupWorker = new NioEventLoopGroup(
+                            nettyServerConfig.getBossThreadPrefix(), nettyServerConfig.getBossThreadSize(), false),
+                    NioIoHandler.newFactory());
+            this.eventLoopGroupWorker = new MultiThreadIoEventLoopGroup(
                     nettyServerConfig.getServerWorkerThreads(),
                     new NamedThreadFactory(
                             nettyServerConfig.getWorkerThreadPrefix(),
                             nettyServerConfig.getServerWorkerThreads(),
-                            false));
+                            false),
+                    NioIoHandler.newFactory());
         }
 
         if (nettyServerConfig.getServerListenPort() > 0) {
@@ -168,8 +174,10 @@ public void start() {
                 .channel(NettyServerConfig.SERVER_CHANNEL_CLAZZ)
                 .option(ChannelOption.SO_BACKLOG, nettyServerConfig.getSoBackLogSize())
                 .option(ChannelOption.SO_REUSEADDR, true)
+                .option(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT)
                 .childOption(ChannelOption.SO_KEEPALIVE, true)
                 .childOption(ChannelOption.TCP_NODELAY, true)
+                .childOption(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT)
                 .childOption(ChannelOption.SO_SNDBUF, nettyServerConfig.getServerSocketSendBufSize())
                 .childOption(ChannelOption.SO_RCVBUF, nettyServerConfig.getServerSocketResvBufSize())
                 .childOption(

diff --git a/core/src/test/java/org/apache/seata/core/rpc/netty/ChannelEventHandlerIntegrationTest.java b/core/src/test/java/org/apache/seata/core/rpc/netty/ChannelEventHandlerIntegrationTest.java
@@ -23,7 +23,8 @@
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelPipeline;
 import io.netty.channel.EventLoopGroup;
-import io.netty.channel.nio.NioEventLoopGroup;
+import io.netty.channel.MultiThreadIoEventLoopGroup;
+import io.netty.channel.nio.NioIoHandler;
 import io.netty.channel.socket.SocketChannel;
 import io.netty.channel.socket.nio.NioServerSocketChannel;
 import io.netty.channel.socket.nio.NioSocketChannel;
@@ -73,8 +74,8 @@ class ChannelEventHandlerIntegrationTest {
 
     @BeforeAll
     static void setupClass() throws InterruptedException {
-        bossGroup = new NioEventLoopGroup(1);
-        workerGroup = new NioEventLoopGroup();
+        bossGroup = new MultiThreadIoEventLoopGroup(1, NioIoHandler.newFactory());
+        workerGroup = new MultiThreadIoEventLoopGroup(NioIoHandler.newFactory());
 
         ServerBootstrap serverBootstrap = new ServerBootstrap();
         serverBootstrap
@@ -107,7 +108,7 @@ static void tearDownClass() {
     void setUp() {
         channelEventHandler = new ChannelEventHandler(mockRemotingClient);
 
-        clientGroup = new NioEventLoopGroup();
+        clientGroup = new MultiThreadIoEventLoopGroup(NioIoHandler.newFactory());
         channelActiveLatch = new CountDownLatch(1);
         channelInactiveLatch = new CountDownLatch(1);
         exceptionCaughtLatch = new CountDownLatch(1);

diff --git a/core/src/test/java/org/apache/seata/core/rpc/netty/NettyClientBootstrapTest.java b/core/src/test/java/org/apache/seata/core/rpc/netty/NettyClientBootstrapTest.java
@@ -16,15 +16,20 @@
  */
 package org.apache.seata.core.rpc.netty;
 
+import io.netty.bootstrap.Bootstrap;
+import io.netty.buffer.PooledByteBufAllocator;
+import io.netty.channel.ChannelOption;
 import io.netty.channel.EventLoopGroup;
+import io.netty.channel.MultiThreadIoEventLoopGroup;
 import io.netty.channel.epoll.Epoll;
 import io.netty.channel.epoll.EpollSocketChannel;
 import io.netty.channel.socket.nio.NioSocketChannel;
-import io.netty.util.internal.PlatformDependent;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
+import org.mockito.MockedStatic;
+import org.mockito.Mockito;
 import org.mockito.junit.jupiter.MockitoExtension;
 
 import static org.mockito.Mockito.when;
@@ -67,18 +72,35 @@ void testSharedEventLoopGroupDisabled() {
     void testStartWithSharedEventLoopAndChannelSelection() {
         when(nettyClientConfig.getEnableClientSharedEventLoop()).thenReturn(true);
         when(nettyClientConfig.getClientChannelClazz()).thenAnswer(invocation -> {
-            if (PlatformDependent.isWindows() || PlatformDependent.isOsx()) {
-                return NioSocketChannel.class;
-            } else if (Epoll.isAvailable()) {
+            if (Epoll.isAvailable()) {
                 return EpollSocketChannel.class;
-            } else {
-                return NioSocketChannel.class;
             }
+            return NioSocketChannel.class;
         });
 
         NettyClientBootstrap tmNettyClientBootstrap =
                 new NettyClientBootstrap(nettyClientConfig, NettyPoolKey.TransactionRole.TMROLE);
         tmNettyClientBootstrap.start();
+
+        Assertions.assertSame(
+                PooledByteBufAllocator.DEFAULT,
+                getBootstrap(tmNettyClientBootstrap).config().options().get(ChannelOption.ALLOCATOR));
+    }
+
+    @Test
+    void testNioEventLoopGroup() {
+        when(nettyClientConfig.getEnableClientSharedEventLoop()).thenReturn(false);
+
+        try (MockedStatic<NettyServerConfig> mockedConfig =
+                Mockito.mockStatic(NettyServerConfig.class, Mockito.CALLS_REAL_METHODS)) {
+            mockedConfig.when(NettyServerConfig::enableEpoll).thenReturn(false);
+
+            NettyClientBootstrap bootstrap =
+                    new NettyClientBootstrap(nettyClientConfig, NettyPoolKey.TransactionRole.TMROLE);
+            EventLoopGroup eventLoopGroup = getEventLoopGroupWorker(bootstrap);
+            Assertions.assertInstanceOf(MultiThreadIoEventLoopGroup.class, eventLoopGroup);
+            eventLoopGroup.shutdownGracefully().syncUninterruptibly();
+        }
     }
 
     private EventLoopGroup getEventLoopGroupWorker(NettyClientBootstrap bootstrap) {
@@ -90,4 +112,14 @@ private EventLoopGroup getEventLoopGroupWorker(NettyClientBootstrap bootstrap) {
             throw new RuntimeException(e);
         }
     }
+
+    private Bootstrap getBootstrap(NettyClientBootstrap bootstrap) {
+        try {
+            java.lang.reflect.Field field = NettyClientBootstrap.class.getDeclaredField("bootstrap");
+            field.setAccessible(true);
+            return (Bootstrap) field.get(bootstrap);
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
 }