RobertIndie opened a new issue, #21838: URL: https://github.com/apache/pulsar/issues/21838
### Search before asking - [X] I searched in the [issues](https://github.com/apache/pulsar/issues) and found nothing similar. ### Version b944f10d2a9bac2fbe19dc83bf250a276f1ed4d1 ### Minimal reproduce step Here is the reproduction code: ```java PulsarAdmin admin = buildAdminClient(); String topic = "test"; admin.topics().createPartitionedTopic(topic, 1); Consumer<byte[]> consumer = pulsarClient.newConsumer() .topic(topic) .subscriptionName("sub") .subscriptionType(SubscriptionType.Shared) .subscriptionInitialPosition(SubscriptionInitialPosition.Earliest) .maxTotalReceiverQueueSizeAcrossPartitions(10) .receiverQueueSize(10) .consumerName("A") .subscribe(); Producer<byte[]> producer = pulsarClient.newProducer() .topic(topic) .enableBatching(false) .create(); for (int i = 0; i < 20; i++) { producer.send(("test" + i).getBytes()); } Message<byte[]> msg = consumer.receive(100, TimeUnit.MILLISECONDS); log.info("Received message: {}", msg.getMessageId()); Thread.sleep(1000); Consumer<byte[]> consumer2 = pulsarClient.newConsumer() .topic(topic) .subscriptionName("sub") .subscriptionType(SubscriptionType.Shared) .subscriptionInitialPosition(SubscriptionInitialPosition.Earliest) .maxTotalReceiverQueueSizeAcrossPartitions(10) .receiverQueueSize(10) .consumerName("B") .subscribe(); msg = consumer2.receive(1000, TimeUnit.MILLISECONDS); Assert.assertNotNull(msg); log.info("Received message: {}", msg.getMessageId()); ``` ### What did you expect to see? According to the documentation for the `maxTotalReceiverQueueSizeAcrossPartitions`: > The purpose of this setting is to have an upper-limit on the number of messages that a consumer can be pushed at once from a broker, across all the partitions. From my understandings, `maxTotalReceiverQueueSizeAcrossPartitions` should be able to control the max number of all cached messages in the consumer. Therefore, looking at the above code, the consumer A should only be able to cache a maximum of 10 messages. The consumer B should be able to receive a new message. ### What did you see instead? But consumer A has actually cached all 20 messages in the receiver queue(receiverQueueSize+maxTotalReceiverQueueSizeAcrossPartitions). Consumer B can't receive the messages. So the above test would fail. ### Anything else? From the implementation, the maximum number of messages actually cached by multi-topics consumer is approximately receiverQueueSize+maxTotalReceiverQueueSizeAcrossPartitions.This seems to go against the case described in the documentation. ### Are you willing to submit a PR? - [X] I'm willing to submit a PR! -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: commits-unsubscr...@pulsar.apache.org.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
