设置线程为守护线程，保证在main线程退出时应用程序能过正常关闭。

api/src/main/java/com/alibaba/nacos/api/remote/RpcScheduledExecutor.java

@@ -17,6 +17,8 @@
 package com.alibaba.nacos.api.remote;
 
 import java.util.concurrent.ScheduledThreadPoolExecutor;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.atomic.AtomicLong;
 
 /**
  * rpc scheduler executor .
@@ -33,7 +35,16 @@ public class RpcScheduledExecutor extends ScheduledThreadPoolExecutor {
  "com.alibaba.nacos.remote.ServerCommonScheduler");
 
  public RpcScheduledExecutor(int corePoolSize, final String threadName) {
- super(corePoolSize, r -> new Thread(r, threadName));
+ super(corePoolSize, new ThreadFactory() {
+ private AtomicLong index = new AtomicLong();
+
+ @Override
+ public Thread newThread(Runnable r) {
+ Thread thread = new Thread(r, threadName + "." + index.getAndIncrement());
+ thread.setDaemon(true);
+ return thread;
+ }
+ });
  }
 
 }

common/src/main/java/com/alibaba/nacos/common/http/AbstractHttpClientFactory.java

@@ -16,6 +16,7 @@
 
 package com.alibaba.nacos.common.http;
 
+import com.alibaba.nacos.common.executor.NameThreadFactory;
 import com.alibaba.nacos.common.http.client.NacosAsyncRestTemplate;
 import com.alibaba.nacos.common.http.client.NacosRestTemplate;
 import com.alibaba.nacos.common.http.client.request.DefaultAsyncHttpClientRequest;
@@ -24,7 +25,9 @@
 import com.alibaba.nacos.common.tls.TlsFileWatcher;
 import com.alibaba.nacos.common.tls.TlsHelper;
 import com.alibaba.nacos.common.tls.TlsSystemConfig;
+
 import java.util.function.BiConsumer;
+
 import org.apache.http.client.config.RequestConfig;
 import org.apache.http.config.Registry;
 import org.apache.http.config.RegistryBuilder;
@@ -58,6 +61,10 @@
  */
 public abstract class AbstractHttpClientFactory implements HttpClientFactory {
 
+ private static final String ASYNC_THREAD_NAME = "nacos-http-async-client";
+
+ private static final String AYNC_IO_REACTOR_NAME = ASYNC_THREAD_NAME + "#I/O Reactor";
+
  @Override
  public NacosRestTemplate createNacosRestTemplate() {
  HttpClientConfig httpClientConfig = buildHttpClientConfig();
@@ -75,68 +82,67 @@ public NacosRestTemplate createNacosRestTemplate() {
  @Override
  public NacosAsyncRestTemplate createNacosAsyncRestTemplate() {
  final HttpClientConfig originalRequestConfig = buildHttpClientConfig();
- final DefaultConnectingIOReactor ioreactor = getIoReactor();
+ final DefaultConnectingIOReactor ioreactor = getIoReactor(AYNC_IO_REACTOR_NAME);
  final RequestConfig defaultConfig = getRequestConfig();
  return new NacosAsyncRestTemplate(assignLogger(), new DefaultAsyncHttpClientRequest(
- HttpAsyncClients.custom()
- .addInterceptorLast(new RequestContent(true))
- .setDefaultIOReactorConfig(getIoReactorConfig())
- .setDefaultRequestConfig(defaultConfig)
+ HttpAsyncClients.custom().addInterceptorLast(new RequestContent(true))
+ .setThreadFactory(new NameThreadFactory(ASYNC_THREAD_NAME))
+ .setDefaultIOReactorConfig(getIoReactorConfig()).setDefaultRequestConfig(defaultConfig)
  .setMaxConnTotal(originalRequestConfig.getMaxConnTotal())
  .setMaxConnPerRoute(originalRequestConfig.getMaxConnPerRoute())
  .setUserAgent(originalRequestConfig.getUserAgent())
- .setConnectionManager(getConnectionManager(originalRequestConfig, ioreactor))
-  .build(), ioreactor, defaultConfig));
+ .setConnectionManager(getConnectionManager(originalRequestConfig, ioreactor)).build(),
+ ioreactor, defaultConfig));
  }
 
- private DefaultConnectingIOReactor getIoReactor() {
+ private DefaultConnectingIOReactor getIoReactor(String threadName) {
  final DefaultConnectingIOReactor ioreactor;
  try {
- ioreactor = new DefaultConnectingIOReactor(getIoReactorConfig());
+ ioreactor = new DefaultConnectingIOReactor(getIoReactorConfig(), new NameThreadFactory(threadName));
  } catch (IOReactorException e) {
  assignLogger().error("[NHttpClientConnectionManager] Create DefaultConnectingIOReactor failed", e);
  throw new IllegalStateException();
  }
-
+ 
  // if the handle return true, then the exception thrown by IOReactor will be ignore, and will not finish the IOReactor.
  ioreactor.setExceptionHandler(new IOReactorExceptionHandler() {
-
+ 
  @Override
  public boolean handle(IOException ex) {
  assignLogger().warn("[NHttpClientConnectionManager] handle IOException, ignore it.", ex);
  return true;
  }
-
+ 
  @Override
  public boolean handle(RuntimeException ex) {
  assignLogger().warn("[NHttpClientConnectionManager] handle RuntimeException, ignore it.", ex);
  return true;
  }
  });
-
+ 
  return ioreactor;
  }
 
  /**
- * create the {@link NHttpClientConnectionManager}, the code mainly from {@link HttpAsyncClientBuilder#build()}.
- * we add the {@link IOReactorExceptionHandler} to handle the {@link IOException} and {@link RuntimeException}
- * thrown by the {@link org.apache.http.impl.nio.reactor.BaseIOReactor} when process the event of Network.
- * Using this way to avoid the {@link DefaultConnectingIOReactor} killed by unknown error of network.
+ * create the {@link NHttpClientConnectionManager}, the code mainly from {@link HttpAsyncClientBuilder#build()}. we
+ * add the {@link IOReactorExceptionHandler} to handle the {@link IOException} and {@link RuntimeException} thrown
+ * by the {@link org.apache.http.impl.nio.reactor.BaseIOReactor} when process the event of Network. Using this way
+ * to avoid the {@link DefaultConnectingIOReactor} killed by unknown error of network.
  *
  * @param originalRequestConfig request config.
- * @param ioreactor I/O reactor.
+ * @param ioreactor  I/O reactor.
  * @return {@link NHttpClientConnectionManager}.
  */
- private NHttpClientConnectionManager getConnectionManager(HttpClientConfig originalRequestConfig, DefaultConnectingIOReactor ioreactor) {
+ private NHttpClientConnectionManager getConnectionManager(HttpClientConfig originalRequestConfig,
+ DefaultConnectingIOReactor ioreactor) {
  SSLContext sslcontext = SSLContexts.createDefault();
  HostnameVerifier hostnameVerifier = new DefaultHostnameVerifier();
  SchemeIOSessionStrategy sslStrategy = new SSLIOSessionStrategy(sslcontext, null, null, hostnameVerifier);
 
  Registry<SchemeIOSessionStrategy> registry = RegistryBuilder.<SchemeIOSessionStrategy>create()
- .register("http", NoopIOSessionStrategy.INSTANCE)
- .register("https", sslStrategy)
- .build();
- final PoolingNHttpClientConnectionManager poolingmgr = new PoolingNHttpClientConnectionManager(ioreactor, registry);
+ .register("http", NoopIOSessionStrategy.INSTANCE).register("https", sslStrategy).build();
+ final PoolingNHttpClientConnectionManager poolingmgr = new PoolingNHttpClientConnectionManager(ioreactor,
+ registry);
 
  int maxTotal = originalRequestConfig.getMaxConnTotal();
  if (maxTotal > 0) {

common/src/main/java/com/alibaba/nacos/common/http/HttpClientBeanHolder.java

@@ -38,8 +38,7 @@ public final class HttpClientBeanHolder {
 
  private static final Map<String, NacosRestTemplate> SINGLETON_REST = new HashMap<>(10);
 
- private static final Map<String, NacosAsyncRestTemplate> SINGLETON_ASYNC_REST = new HashMap<>(
- 10);
+ private static final Map<String, NacosAsyncRestTemplate> SINGLETON_ASYNC_REST = new HashMap<>(10);
 
  private static final AtomicBoolean ALREADY_SHUTDOWN = new AtomicBoolean(false);
 
@@ -101,11 +100,14 @@ private static void shutdown() {
  return;
  }
  LOGGER.warn("[HttpClientBeanHolder] Start destroying common HttpClient");
+
  try {
  shutdown(DefaultHttpClientFactory.class.getName());
  } catch (Exception ex) {
- LOGGER.error("An exception occurred when the common HTTP client was closed : {}", ExceptionUtil.getStackTrace(ex));
+ LOGGER.error("An exception occurred when the common HTTP client was closed : {}",
+ ExceptionUtil.getStackTrace(ex));
  }
+
  LOGGER.warn("[HttpClientBeanHolder] Destruction of the end");
  }
 

common/src/main/java/com/alibaba/nacos/common/task/engine/TaskExecuteWorker.java

@@ -48,6 +48,8 @@ public final class TaskExecuteWorker implements NacosTaskProcessor, Closeable {
 
  private final AtomicBoolean closed;
 
+ private final InnerWorker realWorker;
+
  public TaskExecuteWorker(final String name, final int mod, final int total) {
  this(name, mod, total, null);
  }
@@ -57,7 +59,8 @@ public TaskExecuteWorker(final String name, final int mod, final int total, fina
  this.queue = new ArrayBlockingQueue<>(QUEUE_CAPACITY);
  this.closed = new AtomicBoolean(false);
  this.log = null == logger ? LoggerFactory.getLogger(TaskExecuteWorker.class) : logger;
- new InnerWorker(name).start();
+ realWorker = new InnerWorker(this.name);
+ realWorker.start();
  }
 
  public String getName() {
@@ -95,6 +98,7 @@ public String status() {
  public void shutdown() throws NacosException {
  queue.clear();
  closed.compareAndSet(false, true);
+ realWorker.interrupt();
  }
 
  /**
@@ -119,7 +123,7 @@ public void run() {
  log.warn("task {} takes {}ms", task, duration);
  }
  } catch (Throwable e) {
- log.error("[TASK-FAILED] " + e.toString(), e);
+ log.error("[TASK-FAILED] " + e, e);
  }
  }
  }

core/src/main/java/com/alibaba/nacos/core/distributed/distro/task/DistroTaskEngineHolder.java

@@ -21,6 +21,7 @@
 import com.alibaba.nacos.core.distributed.distro.task.delay.DistroDelayTaskExecuteEngine;
 import com.alibaba.nacos.core.distributed.distro.task.delay.DistroDelayTaskProcessor;
 import com.alibaba.nacos.core.distributed.distro.task.execute.DistroExecuteTaskExecuteEngine;
+import org.springframework.beans.factory.DisposableBean;
 import org.springframework.stereotype.Component;
 
 /**
@@ -29,7 +30,7 @@
  * @author xiweng.yy
  */
 @Component
-public class DistroTaskEngineHolder {
+public class DistroTaskEngineHolder implements DisposableBean {
 
  private final DistroDelayTaskExecuteEngine delayTaskExecuteEngine = new DistroDelayTaskExecuteEngine();
 
@@ -51,4 +52,10 @@ public DistroExecuteTaskExecuteEngine getExecuteWorkersManager() {
  public void registerNacosTaskProcessor(Object key, NacosTaskProcessor nacosTaskProcessor) {
  this.delayTaskExecuteEngine.addProcessor(key, nacosTaskProcessor);
  }
+
+ @Override
+ public void destroy() throws Exception {
+ this.delayTaskExecuteEngine.shutdown();
+ this.executeWorkersManager.shutdown();
+ }
 }

istio/src/main/java/com/alibaba/nacos/istio/common/EventProcessor.java

@@ -39,17 +39,17 @@
  */
 @Component
 public class EventProcessor implements ApplicationListener<ContextRefreshedEvent> {
-
+ 
  private static final int MAX_WAIT_EVENT_TIME = 100;
-
+ 
  private NacosMcpService nacosMcpService;
-
+ 
  private NacosXdsService nacosXdsService;
-
+ 
  private NacosResourceManager resourceManager;
-
+ 
  private final BlockingQueue<Event> events;
-
+ 
  public EventProcessor() {
  events = new ArrayBlockingQueue<>(20);
  }
@@ -68,25 +68,27 @@ public void notify(Event event) {
  Thread.currentThread().interrupt();
  }
  }
-
- public void handleEvents() {
- new Consumer("handle events").start();
+
+ private void handleEvents() {
+ Consumer handleEvents = new Consumer("handle events");
+ handleEvents.setDaemon(true);
+ handleEvents.start();
  }
-
+ 
  @Override
  public void onApplicationEvent(ContextRefreshedEvent contextRefreshedEvent) {
  if (contextRefreshedEvent.getApplicationContext().getParent() == null) {
  checkDependenceReady();
  handleEvents();
  }
  }
-
+ 
  private class Consumer extends Thread {
-
+ 
  Consumer(String name) {
  setName(name);
  }
-
+ 
  @Override
  @SuppressWarnings("InfiniteLoopStatement")
  public void run() {
@@ -115,23 +117,23 @@ public void run() {
  }
  }
  }
-
+ 
  private boolean hasClientConnection() {
  return nacosMcpService.hasClientConnection() || nacosXdsService.hasClientConnection();
  }
-
+ 
  private boolean needNewTask(boolean hasNewEvent, Future<Void> task) {
  return hasNewEvent && (task == null || task.isDone());
  }
-
+ 
  private class EventHandleTask implements Callable<Void> {
-
+ 
  private final Event event;
-
+ 
  EventHandleTask(Event event) {
  this.event = event;
  }
-
+ 
  @Override
  public Void call() throws Exception {
  ResourceSnapshot snapshot = resourceManager.createResourceSnapshot();

naming/src/main/java/com/alibaba/nacos/naming/misc/GracefulShutdownListener.java

@@ -0,0 +1,54 @@
+package com.alibaba.nacos.naming.misc;
+
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.core.listener.NacosApplicationListener;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.core.env.ConfigurableEnvironment;
+
+/**
+ * Graceful shutdown.
+ *
+ * @author Weizhan▪Yun
+ * @date 2022/10/27 16:44
+ */
+public class GracefulShutdownListener implements NacosApplicationListener {
+
+ @Override
+ public void starting() {
+
+ }
+
+ @Override
+ public void environmentPrepared(ConfigurableEnvironment environment) {
+
+ }
+
+ @Override
+ public void contextPrepared(ConfigurableApplicationContext context) {
+
+ }
+
+ @Override
+ public void contextLoaded(ConfigurableApplicationContext context) {
+
+ }
+
+ @Override
+ public void started(ConfigurableApplicationContext context) {
+
+ }
+
+ @Override
+ public void running(ConfigurableApplicationContext context) {
+
+ }
+
+ @Override
+ public void failed(ConfigurableApplicationContext context, Throwable exception) {
+ try {
+ NamingExecuteTaskDispatcher.getInstance().getExecuteEngine().shutdown();
+ } catch (NacosException ignore) {
+
+ }
+ }
+}

naming/src/main/java/com/alibaba/nacos/naming/misc/NamingExecuteTaskDispatcher.java

@@ -46,4 +46,8 @@ public void dispatchAndExecuteTask(Object dispatchTag, AbstractExecuteTask task)
  public String workersStatus() {
  return executeEngine.workersStatus();
  }
+
+ NacosExecuteTaskExecuteEngine getExecuteEngine() {
+ return executeEngine;
+ }
 }

naming/src/main/resources/META-INF/services/com.alibaba.nacos.core.listener.NacosApplicationListener

@@ -0,0 +1 @@
+com.alibaba.nacos.naming.misc.GracefulShutdownListener