重新平衡后停止使用来自新分配分区的消息

Question

bin/kafka-topics.sh --create --zookeeper localhost:2181 --replication-factor 1 --partitions 5 --topic tracking

kafka.servers.bootstrap=localhost:9092 
kafka.topic.tracking=tracking
kafka.group.id=trackingGroup
kafka.client.id=client-1

client-1: partitions assigned:[tracking-4, tracking-3]
client-2: partitions assigned:[tracking-2, tracking-1]
client-3: partitions assigned:[tracking-0]

client-1: partitions assigned:[]
client-2: partitions assigned:[tracking-2,tracking-1, tracking-0]
client-3: partitions assigned:[tracking-4,tracking-3]

我发现分区“Tracking-3”上的消息没有被消耗！！

问题每次都会重现，在新分配的分区中有一些消息丢失，你能有什么建议吗？请帮帮我，谢谢

Answer 1

我复制了它；这看起来像是kafka本身的问题(auto.comit.enabled=true)在重新平衡中，kafka报告未读分区的“位置”(将获取的下一条记录的偏移量（如果存在具有该偏移量的记录）)作为分区的末尾。

事实上，当我使用kafka-consumer-groups工具时，未读分区的偏移量已经在“末尾”了。当我只使用一个用户运行它时，当它读取第一个分区时，我看到...

$ kafka-consumer-groups --bootstrap-server localhost:9092 --describe -group so43405009

TOPIC                          PARTITION  CURRENT-OFFSET  LOG-END-OFFSET  LAG        CONSUMER-ID                                       HOST                           CLIENT-ID
tracking                       0          37              40              3          client1-8129bb3d-3a83-4c83-9128-3a2762ede758      /10.0.0.6                      client1
tracking                       1          40              40              0          client1-8129bb3d-3a83-4c83-9128-3a2762ede758      /10.0.0.6                      client1
tracking                       2          40              40              0          client1-8129bb3d-3a83-4c83-9128-3a2762ede758      /10.0.0.6                      client1
tracking                       3          40              40              0          client1-8129bb3d-3a83-4c83-9128-3a2762ede758      /10.0.0.6                      client1
tracking                       4          40              40              0          client1-8129bb3d-3a83-4c83-9128-3a2762ede758      /10.0.0.6                      client1

注意CURRENT_OFFSET列。

TOPIC                          PARTITION  CURRENT-OFFSET  LOG-END-OFFSET  LAG        CONSUMER-ID                                       HOST                           CLIENT-ID
tracking                       0          41              44              3          client1-56d78a4b-f2df-4e31-8c5d-f8a1d8f64cf8      /10.0.0.6                      client1
tracking                       1          44              44              0          client1-56d78a4b-f2df-4e31-8c5d-f8a1d8f64cf8      /10.0.0.6                      client1
tracking                       2          44              44              0          client1-56d78a4b-f2df-4e31-8c5d-f8a1d8f64cf8      /10.0.0.6                      client1
tracking                       3          44              44              0          client1-56d78a4b-f2df-4e31-8c5d-f8a1d8f64cf8      /10.0.0.6                      client1
tracking                       4          44              44              0          client1-56d78a4b-f2df-4e31-8c5d-f8a1d8f64cf8      /10.0.0.6                      client1

TOPIC                          PARTITION  CURRENT-OFFSET  LOG-END-OFFSET  LAG        CONSUMER-ID                                       HOST                           CLIENT-ID
tracking                       0          44              44              0          client1-56d78a4b-f2df-4e31-8c5d-f8a1d8f64cf8      /10.0.0.6                      client1
tracking                       1          44              44              0          client1-56d78a4b-f2df-4e31-8c5d-f8a1d8f64cf8      /10.0.0.6                      client1
tracking                       2          41              44              3          client1-56d78a4b-f2df-4e31-8c5d-f8a1d8f64cf8      /10.0.0.6                      client1
tracking                       3          44              44              0          client1-56d78a4b-f2df-4e31-8c5d-f8a1d8f64cf8      /10.0.0.6                      client1
tracking                       4          44              44              0          client1-56d78a4b-f2df-4e31-8c5d-f8a1d8f64cf8      /10.0.0.6                      client1

spring.kafka.consumer.enable-auto-commit=false

TOPIC                          PARTITION  CURRENT-OFFSET  LOG-END-OFFSET  LAG        CONSUMER-ID                                       HOST                           CLIENT-ID
tracking                       0          52              52              0          client1-59413599-81e8-49dd-bbd7-8a62152f11e5      /10.0.0.6                      client1
tracking                       1          49              52              3          client1-59413599-81e8-49dd-bbd7-8a62152f11e5      /10.0.0.6                      client1
tracking                       2          49              52              3          client2-edfe34f9-08d5-4825-80d0-4a6cf9526e42      /10.0.0.6                      client2
tracking                       3          48              52              4          client2-edfe34f9-08d5-4825-80d0-4a6cf9526e42      /10.0.0.6                      client2
tracking                       4          51              52              1          client3-20da8742-af38-403e-b125-5d0c7c771319      /10.0.0.6                      client3

@SpringBootApplication
public class So43405009Application implements CommandLineRunner {

    public static void main(String[] args) {
        SpringApplication.run(So43405009Application.class, args);
    }

    @Autowired
    private KafkaTemplate<String, String> template;

    @Value("${spring.kafka.consumer.client-id}")
    private String clientId;

    @Override
    public void run(String... args) throws Exception {
        if (this.clientId.endsWith("1")) {
            for (int i = 0; i < 20; i++) {
                this.template.sendDefault("foo" + i);
            }
        }
    }

    @Bean
    public KafkaMessageListenerContainer<String, String> container(ConsumerFactory<String, String> cf) {
        ContainerProperties containerProperties = new ContainerProperties("tracking");
        containerProperties.setMessageListener((MessageListener<?, ?>) d -> {
            System.out.println(d);
            try {
                Thread.sleep(5_000);
            }
            catch (InterruptedException e) {
                Thread.currentThread().interrupt();
            }
        });
        KafkaMessageListenerContainer<String, String> container = new KafkaMessageListenerContainer<>(cf,
                containerProperties);
        return container;
    }

}

spring.kafka.listener.ack-mode=record
spring.kafka.consumer.enable-auto-commit=false
spring.kafka.consumer.auto-offset-reset=earliest
spring.kafka.consumer.group-id=so43405009
spring.kafka.consumer.client-id=client1
spring.kafka.template.default-topic=tracking

编辑

原来是Spring-Kafka的虫子；它在启用自动提交的情况下工作，但您必须显式启用它

spring.kafka.consumer.enable-auto-commit=true

否则，容器假定它是false，并导致上述奇怪的行为--如果启用了自动提交，那么看起来客户机不喜欢调用使用者的提交方法。#288。