Hi everyone, I'd like to reinitiate the conversation about KIP-977. This KIP was approved and scheduled for release 3.8.0 but appears not to have been shipped.
At Salesforce, we're exploring implementing this KIP (draft PR: [ https://github.com/apache/kafka/pull/20397](https://github.com/apache/kafka/pull/20397)) and are particularly interested in its performance implications. I envision two possible implementations: 1. The approach in our draft PR checks verbosity rules for every request to determine which metrics to emit. This could lead to performance degradation if the rules are complex or if there's a large cluster with many topics, especially when wildcards are involved. Each topic in a request would need to be checked against the rules every time. 2. Alternatively, we could build and maintain a map of topics to metrics in memory for quicker lookups. This map would need to be updated when verbosity configurations change (which is straightforward using `reconfigure`) and when topics are created or removed (I'm unsure if there's a hook for this). I reviewed the original thread ([ https://lists.apache.org/thread/fz1bqj84fl2st20s9rrwy4tv0jhrpo33](https://lists.apache.org/thread/fz1bqj84fl2st20s9rrwy4tv0jhrpo33)) but couldn't find specific implementation details. Looking forward to your thoughts. Best, Afshin
