Use SKIP LOCKED instead of NOWAIT in mini scheduler

[VladimirYushkevich]

Related: #39680
In this changed argument from nowait to skip_locked for dag_run query. This allows to not rise DB error.

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[dstandish]

Related: #39680 In this changed argument from nowait to skip_locked for dag_run query. This allows to not rise DB error.

Hi can you please share error you are getting and repro steps?

Is it an uncaught error or just a logged exception?

thanks

[Taragolis]

@dstandish this error happen on DB backend, e.g Postgres:

• Postgres is raising lock errors when using more than 1 Airflow scheduler replica #39781
• Dynamically Mapped Tasks: DB performance issues #39680

[dstandish]

I know but it should be caught

[VladimirYushkevich]

I know but it should be caught

But the problem is this error produces unnecessary noise(with ERROR severity) in Postgres DB. That creates alerts, notifications, etc...

[dstandish]

I know but it should be caught

But the problem is this error produces unnecessary noise(with ERROR severity) in Postgres DB. That creates alerts, notifications, etc...

I see, sure, makes sense

[potiuk]

Looks good @dstandish - are you good with it ? Avoiding server-side error is worth it.

[boring-cyborg]

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