Hi folks We have been working on overhauling FairScheduler preemption on branch YARN-4572. It is close to being ready for merge to trunk:
1. Preemption considers individual ResourceRequests to satisfy. (YARN-5605) 2. Preemption now works within a leaf queue and across sibling leaf queues. (YARN-5605) 3. Comprehensive unit tests for app starvation and preemption - minshare and fairshare. (YARN-5783 and YARN-5819, the latter is close to commit) 4. TODO: Clean up the TODOs to remove my initials and replace them with appropriate JIRAs. There are some unresolved sub-tasks in the umbrella JIRA, but none of them are regressions in the new implementation. I just uploaded the cumulative patch to YARN-4752 for Jenkins verification and will follow up on any issues that come up. Would like to hear your thoughts on the merge. Thanks Karthik PS: Post facto, I feel a feature branch was unnecessary for this work. Github PRs with multiple commits for ease of review would have been enough.
