shibd opened a new issue, #22866: URL: https://github.com/apache/pulsar/issues/22866
### Search before asking - [X] I searched in the [issues](https://github.com/apache/pulsar/issues) and found nothing similar. ### Motivation We have observed that using Individual ack frequently results in young generation GC and relatively high GC pauses. <img width="668" alt="image" src="https://github.com/apache/pulsar/assets/33416836/0a2634a4-39f0-4d4d-b3a1-5e952173f321"> - Resource: k8s cluster - broker(1.5CPU)(3CPU 8Gi) - bookie(2.5CPU 8Gi) 250Gi gp3 ssd - zookeeper(1CPU 4Gi) - Version: 3.2.2 Performance cmd: ``` bin/pulsar-perf consume test-c 1200 -n 10 -st Shared -t 10 bin/pulsar-perf produce test-p -s 100 -time 1200 -n 10 -t 10 -ml 256M ``` ### Solution The issue should be caused by the large long[] allocated by bitmap. The allocation invoking chain. <img width="1797" alt="image" src="https://github.com/apache/pulsar/assets/33416836/6d559f3d-e0fa-4725-85ae-21a8bd9083f5"> <img width="1702" alt="image" src="https://github.com/apache/pulsar/assets/33416836/18bda1be-6dd0-4e6f-bfc3-6d17b7b60c8d"> Maybe this is a normal phenomenon and can be solved by increasing the CPU, I would like to share it here to see if there are any similar problems and suggestions in the community. ### Alternatives _No response_ ### Anything else? _No response_ ### Are you willing to submit a PR? - [ ] I'm willing to submit a PR! -- 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: commits-unsubscr...@pulsar.apache.org.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org