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[Doc] "negatively acknowledged cumulatively" ambiguous? #18208
Description
Search before asking
- I searched in the issues and found nothing similar.
What issue do you find in Pulsar docs?
This website:
https://pulsar.apache.org/docs/concepts-messaging/#negative-acknowledgement
The:
Messages are negatively acknowledged individually or cumulatively, depending on the consumption subscription type.
The inner "opened indispensable cumulatively", does it have this function in pulsar? At least I did not find the corresponding API for this function.
I don't know if there is some ambiguity in the document, or if there is some problem with my understanding.
In addition:
In Exclusive and Failover subscription types, consumers only negatively acknowledge the last message they receive.
In Shared and Key_Shared subscription types, consumers can negatively acknowledge messages individually.
Are these two paragraphs necessary? In fact, it is the feature of four subscription types, namely whether there is one consumer or how many consumers, and it feels like adding these two paragraphs adds complexity to this technical point.
What is your suggestion?
?
Any reference?
No response
Are you willing to submit a PR?
- I'm willing to submit a PR!
Activity
startjava commentedon Oct 26, 2022
Actually I want to know what situation belongs to "the acknowledged cumulatively"?
thank you !
zymap commentedon Nov 15, 2022
Do you want this? https://pulsar.apache.org/docs/concepts-messaging#acknowledgement
startjava commentedon Nov 15, 2022
YES，i see the doc too .
startjava commentedon Nov 16, 2022
@momo-jun please see the question
momo-jun commentedon Nov 22, 2022
I don't see the ambiguity in this paragraph. It means the negative acknowledgment of messages can be performed either individually (in Shared and Key_Shared subscription types) or cumulatively (Exclusive and Failover subscription types).
Did this answer your question? @startjava
startjava commentedon Nov 22, 2022
@momo-jun
question1：
why
（1）individually (in Shared and Key_Shared subscription types)
（2）cumulatively (Exclusive and Failover subscription types).
why bottom is error：
（1）cumulatively (in Shared and Key_Shared subscription types)
（2）individually (Exclusive and Failover subscription types).
question2：
but not have about "negatively acknowledged cumulatively" api，only have "negatively acknowledged individually" api(Consumer.negativeAcknowledeg)
i have 2 question
thank you jun !
labuladong commentedon Nov 29, 2022
You can try
negativeAcknowledgeinFailover/Exclusivesubscription types. All the messages the consumer didn't acknowledge will be redelivered, this behavior could be negatively acknowledged cumulatively. But there do have some discussions about the redelivery behavior onFailover/Exclusivesubscription types, see https://lists.apache.org/thread/vdwhg5wrpjc8x41oqwxrsdhx7dmyzt3jstartjava commentedon Nov 29, 2022
but i don't know what mean "negatively acknowledged cumulatively"。
momo-jun commentedon Nov 29, 2022
You can understand it as "Cumulative NACK" - the negative acknowledgement is performed cumulatively, that is, consumers only negatively acknowledge the last message they receive.