我正在使用kafka-clients-0.8.2.1.jar，发现当集群根本没有启动时，发送会阻塞。我在网上找到了更多相关信息Kafka 0.8.2 new producer blocking on metadata，发现它是许多人面临的已知问题。 但是我尝试了那里提到的一些选项，但没有帮助： 1.调用KafkaProducer.partitionsFor（），它仍然被阻止。 2.将producer.type设置为async但无法识别。
我想要实现的是检测群集已关闭，排队消息（具有最大限制）并在群集恢复时发送。如果它过于复杂，至少它不会被阻止，因为它会导致应用程序排队所有消息并耗尽内存。
代码：
System.out.println("props:"
producer = new KafkaProducer<String, String>(props);
producer.partitionsFor(record.topic());
producer.send(record, new Callback() {
日志：
props:{queue.size=1000, reconnect.backoff.ms=10000, request.timeout.ms=1000, bootstrap.servers=tstaapp001:59092,ewdlxsrv283:59092,devcapp001:59092, value.serializer=org.apache.kafka.common.serialization.StringSerializer, request.required.acks=1, buffer.memory=33554432, retries=0, producer.type=async, key.serializer=org.apache.kafka.common.serialization.StringSerializer, linger.ms=1, topic.metadata.refresh.interval.ms=1000, batch.size=16384, timeout.ms=10000}
20:44:33.584 [RTEMPool-1-RTEMThread-4] DEBUG o.a.k.c.producer.internals.Metadata - Updated cluster metadata version 1 to Cluster(nodes = [Node(tstaapp001, 59092), Node(devcapp001, 59092), Node(ewdlxsrv283, 59092)], partitions = [])
20:44:33.603 [kafka-producer-network-thread | producer-1] DEBUG o.a.k.c.producer.internals.Sender - Starting Kafka producer I/O thread.
20:44:33.603 [RTEMPool-1-RTEMThread-4] WARN o.a.k.c.producer.ProducerConfig - The configuration topic.metadata.refresh.interval.ms = null was supplied but isn't a known config.
20:44:33.603 [RTEMPool-1-RTEMThread-4] WARN o.a.k.c.producer.ProducerConfig - The configuration request.timeout.ms = null was supplied but isn't a known config.
20:44:33.603 [RTEMPool-1-RTEMThread-4] WARN o.a.k.c.producer.ProducerConfig - The configuration producer.type = null was supplied but isn't a known config.
20:44:33.604 [RTEMPool-1-RTEMThread-4] WARN o.a.k.c.producer.ProducerConfig - The configuration request.required.acks = null was supplied but isn't a known config.
20:44:33.604 [RTEMPool-1-RTEMThread-4] WARN o.a.k.c.producer.ProducerConfig - The configuration queue.size = null was supplied but isn't a known config.
20:44:33.604 [RTEMPool-1-RTEMThread-4] DEBUG o.a.k.clients.producer.KafkaProducer - Kafka producer started
20:44:42.958 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:42.959 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Init connection to node -2 for sending metadata request in the next iteration
20:44:42.959 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Initiating connection to node -2 at ewdlxsrv283:59092.
20:44:42.964 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:43.063 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:43.163 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:43.264 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:43.364 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:43.464 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:43.564 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:43.664 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:43.764 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:43.864 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:43.964 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:44.064 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:44.164 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:44.264 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:44.364 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:44.464 [kafka-producer-network-thread | producer-1] DEBUG o.apache.kafka.clients.NetworkClient - Trying to send metadata request to node -2
20:44:44.479 [kafka-producer-network-thread | producer-1] WARN o.a.kafka.common.network.Selector - Error in I/O with null
java.net.ConnectException: Connection refused: no further information
答案 0 :(得分：2)
新的生产者API将在其内部缓冲区已满时阻止（这没有详细记录）。您可以将属性block.on.buffer.full添加到false，然后您将获得BufferExhaustedException。
请参阅http://kafka.apache.org/082/documentation.html#producerapi