AndyJiang99 opened a new pull request, #3638: URL: https://github.com/apache/gobblin/pull/3638
Dear Gobblin maintainers, Please accept this PR. I understand that it will not be reviewed until I have checked off all the steps below! Helix instances are purged during startup of the yarn service. This operation must be done without new helix instances being added or removed (i.e. the API call is not thread safe). The current implementation blocks the yarn service from allocating initial containers while the helix instance purging is enabled, but it does not prevent other external services from requesting containers through its public methods. These 2 services start up concurrently, and it's possible that the AutoScalingYarnManager starts up before the Yarn Service is completely finished purging. This means leads to the AutoScalingYarnManager to requestContainers while the instances are still purging. This change makes the yarn service start up synchronous and also adds a flag to indicate if start up is complete. This flag is switched when the yarn service has completed start up. The requestTargetNumberOfContainers function will read this flag to see if yarn service startup is completed. This prevents the requestContainers to execute prior to the completion of yarn service startup and prevents a race condition. ### JIRA - [ ] My PR addresses the following [Gobblin JIRA](https://issues.apache.org/jira/browse/GOBBLIN/) issues and references them in the PR title. For example, "[GOBBLIN-XXX] My Gobblin PR" - https://issues.apache.org/jira/browse/GOBBLIN-1781 ### Description - [ ] Here are some details about my PR, including screenshots (if applicable): ### Tests - [ ] My PR adds the following unit tests __OR__ does not need testing for this extremely good reason: ### Commits - [ ] My commits all reference JIRA issues in their subject lines, and I have squashed multiple commits if they address the same issue. In addition, my commits follow the guidelines from "[How to write a good git commit message](http://chris.beams.io/posts/git-commit/)": 1. Subject is separated from body by a blank line 2. Subject is limited to 50 characters 3. Subject does not end with a period 4. Subject uses the imperative mood ("add", not "adding") 5. Body wraps at 72 characters 6. Body explains "what" and "why", not "how" -- 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]
