lianetm commented on PR #18590: URL: https://github.com/apache/kafka/pull/18590#issuecomment-2611089054
Hey here, I don't quite get how the `pollOnClose` approach will solve the issue, basically because it still leaves a lot of time for unneeded FindCoord to be generated and block the network thread close, doesn't it? The `pollOnClose` runs when we're closing the network thread, actually right before we block on `sendUnsentRequests`. This means that we may have already a `FindCoord` generated after the consumer close committed and left the group, correct? To find a solution, let's look at the classic consumer first, this is my understanding: - it does attempt to FindCoord to commit on close of course, here: https://github.com/apache/kafka/blob/40890faa1bed8296919a7e108937ec559d901348/clients/src/main/java/org/apache/kafka/clients/consumer/internals/ConsumerCoordinator.java#L980-L982 (both commit sync and the pending async attempt to find if needed). - it does not attempt to FindCoord when attempting to `maybeLeaveGroup`. After the commit on close phase completes, the classic shutdowns the HB thread (so no more pro-active FindCoord), and then sends the leave req (only if there is a known coord, no-op if it's unknown) https://github.com/apache/kafka/blob/40890faa1bed8296919a7e108937ec559d901348/clients/src/main/java/org/apache/kafka/clients/consumer/internals/AbstractCoordinator.java#L1170 Correct me there, but if that's the behaviour, could it be achieved in the new consumer by allowing the `autoCommitOnClose` run with the background ensuring a coordinator, but right after signaling to the CoordinatorReq manager that it's closing, so it does not generate any more FindCoord? That's what comes to mind, but let me know your thoughts. Thanks! -- 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: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org