kumarUjjawal commented on issue #25148: URL: https://github.com/apache/datafusion/issues/25148#issuecomment-6448420419
## Rollout plan for merge queue cleanup (#26760) #26760 adds the **Merge queue cleanup** workflow. The workflow finds unfinished merge queue runs whose queue branch was removed or now points to a different commit. After the merge, the workflow only reports candidates. It does not cancel runs until a maintainer enables it. ### 1. Observe for at least one week 1. Merge #26760. Do not set `MERGE_QUEUE_CLEANUP_ENABLED`. 2. Let the workflow run for at least one week. It runs for each new merge group and every 15 minutes. 3. Read the "Would cancel merge-group runs" table in each run summary. Each row gives the run ID, SHA, attempt, reason and UTC observation time. 4. Compare each candidate with the real outcome of its queue entry and workflow run. ### 2. Check the results before you enable cancellation - Make sure that there are no false candidates. Each candidate must belong to a group that left the queue or that a new group replaced. It must not belong to an active group or to a merged commit. - Make sure that reruns (attempt 2 or higher) never appear as candidates. - Measure the delay between the creation of a replacement group and the scan that finds the old group. - Count how often the `merge_group` scan finds candidates. If it almost never finds any, remove the `merge_group` trigger and keep the 15-minute schedule. - Look for failed scans. For example, a scan fails if a run listing reaches the 1,000-result cap. Dry runs measure detection only. They do not measure cancellation latency or runner shutdown cost. ### 3. Enable cancellation 1. Set the repository Actions variable `MERGE_QUEUE_CLEANUP_ENABLED` to `true`. 2. Read the first scan summaries after the change. The table title changes to "Requested merge-group cancellations". 3. Find out if a cancelled queued job releases a `runs-on` instance that is already starting. This decides how much of the estimated saving is real. 4. A scheduled scan can fail when it and a `merge_group` scan cancel the same run at the same time. Count how often this happens. 5. Compare the merge queue runner time before and after the change. ### 4. Stop cancellation - To go back to observation mode, remove the variable or set it to `false`. - To stop all scans, disable the workflow in GitHub Actions. -- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
