pingzh opened a new pull request #11875: URL: https://github.com/apache/airflow/pull/11875
Context: when a dag file is under processing and multiple callbacks are created either via zombies or executor events, the dag file is added to the _file_path_queue and the manager will launch a new process to process it, which it should not since the dag file is currently under processing. This will bypass the _parallelism eventually especially when it takes long time to process some dag files. We have seen ~200 dag processors on the scheduler even we set the _parallelism as 60. More dag file processors make CPU spike and in turn it makes the dag file processing even slower. In the end, the scheduler is taken down. <!-- Thank you for contributing! Please make sure that your code changes are covered with tests. And in case of new features or big changes remember to adjust the documentation. Feel free to ping committers for the review! In case of existing issue, reference it using one of the following: closes: #ISSUE related: #ISSUE How to write a good git commit message: http://chris.beams.io/posts/git-commit/ --> --- **^ Add meaningful description above** Read the **[Pull Request Guidelines](https://github.com/apache/airflow/blob/master/CONTRIBUTING.rst#pull-request-guidelines)** for more information. In case of fundamental code change, Airflow Improvement Proposal ([AIP](https://cwiki.apache.org/confluence/display/AIRFLOW/Airflow+Improvements+Proposals)) is needed. In case of a new dependency, check compliance with the [ASF 3rd Party License Policy](https://www.apache.org/legal/resolved.html#category-x). In case of backwards incompatible changes please leave a note in [UPDATING.md](https://github.com/apache/airflow/blob/master/UPDATING.md). ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: [email protected]
