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1. General Let's first look at the polling mechanism in the consumption process of RocketMQ. First, we need to add some pre knowledge related to consumption. 1.1 message consumption mode RocketMQ supports a variety of consumption modes, including Push mode and Pull mode Pull mode: users pull messages and update consumption progressPush mode ...

An InterruptException occurred when the RocketMQConsumer service was shut down Background summary The main problem is the version upgrade Old version core rocketmq dependency <dependency> <groupId>org.apache.rocketmq</groupId> <artifactId>spring-boot-starter-rocketmq</artifactId> <version>${ve ...

Technical work should be rewarded follow+Click three times (like, comment, collect) and watch again to form a good habit RocketMQ tutorial related series directory catalogue Section I: server preparation Section 2: installing RocketMQ Create rocketmq storage directory Modify runbroker sh Modify runserver sh Section III: Configuration ...

consumer.registerMessageListener(new MessageListenerOrderly() { @Override public ConsumeOrderlyStatus consumeMessage(List<MessageExt> msgs, ConsumeOrderlyContext context) { for (MessageExt msg : msgs) { System.out.println(new String(msg.getBody())+" Thread:"+Thread.currentThread( ...

1. Transaction scenario Scenario: ICBC user A transfers 10000 yuan to CCB user B; Steps: 1. ICBC system sends a synchronization message M to Broker, which increases the payment of RMB 10000 to B2. After the message is successfully received by the Broker, send a successful ACK to the ICBC system3. ICBC system will deduct 10000 yuan from u ...

1 Introduction to roles Producer: The sender of the message; Example: SenderConsumer: Message recipient; Example: RecipientBroker: Stay and transfer messages; Example: Post OfficeNameServer: Manage Broker; Examples: the administrative bodies of various post officesTopic: Differentiate the types of messages; One sender can send a message to one ...

1. Retry of sequential messages For sequential messages, when the consumer fails to consume the message, the message queue RocketMQ will automatically retry the message continuously (with an interval of 1 second). At this time, the application will be blocked in message consumption. Therefore, when using sequential messages, it is important to ...

As shown in the title, this paper focuses on sequential messages, delayed messages and message filtering.1, Sequential messageRocketMQ can only ensure the order of messages at the queue level. If you want to realize the sequential execution of a certain type of messages, you must send such messages to the same queue. You can use MessageQueueSel ...

For data storage, RocketMQ uses the file programming model. In order to improve the writing performance of files, the memory mapping mechanism is usually introduced. The data is written to the page cache first, and then the page cache data is flushed to the disk. The performance and data reliability involved in writing must be considered. For t ...

The above is a picture found on the official website. After the producer sends the message, the broker generates the commitlog and ConsumerQueue files, and then the consumer obtains the message according to the starting physical address + message size in the commitlog in the ConsumerQueue, and then obtains the message for consumption.The follow ...