bump 太上玄元道君 <dao...@apache.org> 于2024年4月11日周四 18:20写道：
> Hi, Pulsar community, > > I'm opening this thread to discuss the retention policy for managed > ledgers. > > Currently, the retention policy is defined as a time/size-based policy to > retain messages in the ledger, but there is a difference between the > official documentation and the actual code implementation. > > The official documentation states that the retention policy is to retain > the messages that were *acknowledged*. For example, if the retention size > is set to 10GB and there are 20GB of messages acknowledged, Pulsar will > retain 10GB and delete the rest. > > However, the actual code implementation is different. It retains the > messages that were *written* to the ledger, including *backlog messages* > and *acknowledged messages*. For instance, if there are 10GB of messages in > the backlog and 10GB of messages were acknowledged: > 1. If the retention size is set to 10GB, Pulsar will only retain the 10GB > of messages in the backlog, and the 10GB of messages that were acknowledged > will be deleted. > 2. If the retention size is set to 20GB, Pulsar will retain the 10GB of > messages in the backlog and the 10GB of messages that were acknowledged. > 3. If the retention size is set to 5GB, Pulsar will retain the 10GB of > messages in the backlog, but the 10GB of messages that were acknowledged > will be deleted. > 4. If the retention size is set to 15GB, Pulsar will retain the 10GB of > messages in the backlog and the 5GB of messages that were acknowledged. The > rest of the acknowledged messages will be deleted. > > From Pulsar open source to the present, the code implementation has never > changed, but the meaning of the official documentation has gradually > shifted. So I'm just considering which one is better: the official > documentation or the code implementation? Does the change in the meaning of > the document align more with expectations? Does it indicate that users want > to retain the messages that were acknowledged? > > For a long time, users have believed that the Retention Policy is for > retaining messages that were acknowledged. If we change the document to > match the code implementation, will it meet users' expectations? > > What should we do? Change the document to match the code implementation or > change the code implementation to match the document? > > Regards, > Tao Jiuming >
