RabbitMq Consumer thread error, thread abort.异常导致服务关闭问题

问题描述

在使用rabbitMq消费者使用simple模式进行监听时，服务突然自动关闭，事前没有任何的cpu或者内存的报警。

查看关闭服务前的日志发现OOM异常

Consumer thread error, thread abort.

但是一个异常为什么会导致服务关闭呢？

开始看到OOM，我就想着启动参数上加了当发生OOM时生成堆的dump文件，然而查看文件目录，发现并没有看到生成的堆dump文件，这就十分奇怪

问题分析

后仔细看了报错日志

报错位置是org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.AsyncMessageProcessingConsumer#run

	@Override // NOSONAR - complexity - many catch blocks
		public void run() { // NOSONAR - line count
			if (!isActive()) {
				return;
			}

			boolean aborted = false;

			this.consumer.setLocallyTransacted(isChannelLocallyTransacted());

			String routingLookupKey = getRoutingLookupKey();
			if (routingLookupKey != null) {
				SimpleResourceHolder.bind(getRoutingConnectionFactory(), routingLookupKey); // NOSONAR both never null
			}

			if (this.consumer.getQueueCount() < 1) {
				if (logger.isDebugEnabled()) {
					logger.debug("Consumer stopping; no queues for " + this.consumer);
				}
				SimpleMessageListenerContainer.this.cancellationLock.release(this.consumer);
				if (getApplicationEventPublisher() != null) {
					getApplicationEventPublisher().publishEvent(
							new AsyncConsumerStoppedEvent(SimpleMessageListenerContainer.this, this.consumer));
				}
				this.start.countDown();
				return;
			}

			try {
				initialize();
				while (isActive(this.consumer) || this.consumer.hasDelivery() || !this.consumer.cancelled()) {
					mainLoop();
				}
			}
			catch (InterruptedException e) {
				logger.debug("Consumer thread interrupted, processing stopped.");
				Thread.currentThread().interrupt();
				aborted = true;
				publishConsumerFailedEvent("Consumer thread interrupted, processing stopped", true, e);
			}
			catch (QueuesNotAvailableException ex) {
				logger.error("Consumer threw missing queues exception, fatal=" + isMissingQueuesFatal(), ex);
				if (isMissingQueuesFatal()) {
					this.startupException = ex;
					// Fatal, but no point re-throwing, so just abort.
					aborted = true;
				}
				publishConsumerFailedEvent("Consumer queue(s) not available", aborted, ex);
			}
			catch (FatalListenerStartupException ex) {
				logger.error("Consumer received fatal exception on startup", ex);
				this.startupException = ex;
				// Fatal, but no point re-throwing, so just abort.
				aborted = true;
				publishConsumerFailedEvent("Consumer received fatal exception on startup", true, ex);
			}
			catch (FatalListenerExecutionException ex) { // NOSONAR exception as flow control
				logger.error("Consumer received fatal exception during processing", ex);
				// Fatal, but no point re-throwing, so just abort.
				aborted = true;
				publishConsumerFailedEvent("Consumer received fatal exception during processing", true, ex);
			}
			catch (PossibleAuthenticationFailureException ex) {
				logger.error("Consumer received fatal=" + isPossibleAuthenticationFailureFatal() +
						" exception during processing", ex);
				if (isPossibleAuthenticationFailureFatal()) {
					this.startupException =
							new FatalListenerStartupException("Authentication failure",
									new AmqpAuthenticationException(ex));
					// Fatal, but no point re-throwing, so just abort.
					aborted = true;
				}
				publishConsumerFailedEvent("Consumer received PossibleAuthenticationFailure during startup", aborted, ex);
			}
			catch (ShutdownSignalException e) {
				if (RabbitUtils.isNormalShutdown(e)) {
					if (logger.isDebugEnabled()) {
						logger.debug("Consumer received Shutdown Signal, processing stopped: " + e.getMessage());
					}
				}
				else {
					logConsumerException(e);
				}
			}
			catch (AmqpIOException e) {
				if (e.getCause() instanceof IOException && e.getCause().getCause() instanceof ShutdownSignalException
						&& e.getCause().getCause().getMessage().contains("in exclusive use")) {
					getExclusiveConsumerExceptionLogger().log(logger,
							"Exclusive consumer failure", e.getCause().getCause());
					publishConsumerFailedEvent("Consumer raised exception, attempting restart", false, e);
				}
				else {
					logConsumerException(e);
				}
			}
			catch (Error e) { //NOSONAR
				logger.error("Consumer thread error, thread abort.", e);
				publishConsumerFailedEvent("Consumer threw an Error", true, e);
				getJavaLangErrorHandler().handle(e);
				aborted = true;
			}
			catch (Throwable t) { //NOSONAR
				// by now, it must be an exception
				if (isActive()) {
					logConsumerException(t);
				}
			}
			finally {
				if (getTransactionManager() != null) {
					ConsumerChannelRegistry.unRegisterConsumerChannel();
				}
			}

			// In all cases count down to allow container to progress beyond startup
			this.start.countDown();

			killOrRestart(aborted);

			if (routingLookupKey != null) {
				SimpleResourceHolder.unbind(getRoutingConnectionFactory()); // NOSONAR never null here
			}
		}

辛亏之前度过rabbitMq监听的相关源码，我知道这是消费者线程执行开始执行的地方，在mainLoop中循环消费消息。如果消费发生异常抛出，那么被catch住后会发布事件publishConsumerFailedEvent

spring在处理这个事件后会进行服务的关闭。

原来这里的OOM是调用别的服务，别的服务抛出的。这个异常又没有捕获，抛到SimpleMessageListenerContainer中的run方法触发了关闭服务的事件。
查看了监听器的方法后

发现对异常做了捕捉

try{
}catch (Exception exception) {
            log.error("exception occur={}", exception);
} finally {
            channel.basicAck(message.getMessageProperties().getDeliveryTag(), false);
     }

发现采用的是手动ack的模式。并且对Exception做了异常捕获，那么上面的异常时怎么抛到SimpleMessageListenerContainer中的

原来是因为OutOfMemoryError并不继承自Exception

如果也想捕捉Error异常

还需要加一个捕获

try{
}catch (Exception exception | Error error) {
            log.error("exception={},error={}", exception,error);
} finally {
            channel.basicAck(message.getMessageProperties().getDeliveryTag(), false);
     }

结论

因此在采用手动ack模式时，一定要保证异常/错误不要抛出线程