Documentation FAQ acks_late vs retry seems contradictory

[caspervdw]

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Description

The FAQ section on retry vs acks_late (https://docs.celeryproject.org/en/latest/faq.html#should-i-use-retry-or-acks-late) states that

The acks_late setting would be used when you need the task to be executed again if the worker (for some reason) crashes mid-execution.

While the main docs (https://docs.celeryproject.org/en/stable/userguide/tasks.html#tasks) state:

Note that the worker will acknowledge the message if the child process executing the task is terminated (either by the task calling sys.exit(), or by signal) even when acks_late is enabled.

This seems to be in contradiction. In my own experience, the task is never retried automatically, also not with acks_late=True (so the answer in the FAQ is confusing to me)

Suggestions

I am not expert on all the intricacies of the different workers, but I think the answer in the FAQ should be more precise on what kinds of crashes (and what types workers) will result in an automatic retry when acks_late=True.

[swuecho]

1. if the worker (for some reason) crashes mid-execution. - Yes
2. task throw exception - No https://stackoverflow.com/questions/34029222/does-a-timeout-exception-ack-a-task-with-acks-late

[auvipy]

any improvement request is always welcome