Hi all, Hope you are well, currently, we are exposing the topic metrics with an open one label topic which is the complete topic name such as `persistent://public/default/xxx-partition-0`, but as https://github.com/apache/pulsar/issues/11432 mentioned, we are not able to have an aggregated metrics for the partitioned topic, so PR https://github.com/apache/pulsar/pull/12225 will improve this case which can allow users to expose 2 labels, topic, and partition.
But in order not to break compatibility, I have added an option ` splitTopicAndPartitionLabelInPrometheus` to enable the separate partition label and by default, it should be false. So it's a 2 step upgrade story, upgrade the broker, and enable the option. I want to start a discussion for can we remove the option in 2.9? we have many options and for the new major version, we do not want users to have an option for the single label for 2 labels. Since we should ship the enhancement in branch-2.8, so I have merged the PR which I can cherry-pick to branch-2.8. If we agree to remove the option in 2.9.0, I can push a PR to remove the option in the master branch. Thanks, Penghui
