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Create pull requests: https://help.github.com/articles/creating-a-pull-request/.
Pull requests are made to apache/hadoop
repository on Github. In the Github UI you should pick the trunk branch to target the PR as described for committers. This will be reviewed and commented on so the merge is not automatic. This can be used for discussing a contributions in progress.
How to run Jenkins precommit job for a PR (committers)
Jenkins precommit job is automatically run for the PRs created by committers, but not run for the PRs created by non-committers. If you are a committer and want to run Jenkins precommit job manually, log in to https://builds.apache.org/view/H-L/view/Hadoop/job/hadoop-multibranch/ and click "Scan Repository Now" link.
Merging a PR (yours or contributors)
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