Nataneljpwd opened a new pull request, #64109:
URL: https://github.com/apache/airflow/pull/64109
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We have been experiencing severe dagrun starvation at our cluster, where
when there were a lot of dagruns, and a low max_active_runs limit (hundreds to
thousands runs with a limit in the 10s) this caused a lot of dags to get stuck
in queued state without moving to running, causing those dagruns to timeout.
After investigation, we found that the reason was due to the
_start_queued_dagruns method, where the query was returning dagruns which
cannot be set to running due to the max_active_runs limit, meaning that other
dagruns where starved.
A similar issue occurs when new dagruns are created in large batches (due to
the nulls first), yet this is out of scope for the given pr, I will submit an
additional PR soon.
closes #49508
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