kfaraz opened a new pull request, #20706:
URL: https://github.com/apache/druid/pull/20706
### Changes
- Always consider a scale up or scale down during task rollover irrespective
of the scaling cooldown.
- Since the tasks are being restarted anyway, we might as well choose a
better task count.
- Reset scaling cooldown (driven by `minScaleUpDelay` / `minScaleDownDelay`)
on task rollover.
- Otherwise, if the cooldown elapses soon after the task rollover has
finished, we would go through another round of task restart.
- Rapid successive restarts often lead to unnecessary lag buildup and may
even cause task failures in case of slow segment publish.
- The whole point of the cooldowns is to avoid such task churn.
- Minor cleanup of the `DynamicAllocationTasksNotice`
### Pending
- Add a couple of UTs for the changes in the flow
<hr>
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- [ ] added integration tests.
- [ ] been tested in a test Druid cluster.
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