codelipenghui opened a new pull request, #16160: URL: https://github.com/apache/pulsar/pull/16160
### Motivation The consumer will apply the default batch receive policy even if the user will not use the batch receive API. https://github.com/apache/pulsar/blob/6704f12104219611164aa2bb5bbdfc929613f1bf/pulsar-client-api/src/main/java/org/apache/pulsar/client/api/BatchReceivePolicy.java#L60-L61 This will consume lots of CPU if the client has many consumers (100k consumers) <img width="1846" alt="image" src="https://user-images.githubusercontent.com/12592133/174783886-a4da085d-2cb8-4153-ba96-19414be65502.png";> [consumer-cpu-threads.html.txt](https://github.com/apache/pulsar/files/8948238/consumer-cpu-threads.html.txt) The Pulsar perf tool can also reproduce the problem if run the test with many consumers ### Modification If there is no pending batch receive operation for a consumer, no need to trigger the batch timeout task periodically. We can only start the timeout check after adding batch receive request to pending request queue. Remove the lock in MultiTopicsConsumerImpl as #10352 does ### Verification Added new test to verify the batch receive timeout task will not start if no batch receive request ### Documentation Check the box below or label this PR directly. Need to update docs? - [ ] `doc-required` (Your PR needs to update docs and you will update later) - [x] `doc-not-needed` (Please explain why) - [ ] `doc` (Your PR contains doc changes) - [ ] `doc-complete` (Docs have been already added) -- 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: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
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