[issue46871] Lambda can't be pickled with "spawn" and only "fork"

Change by Kyle Smith : -- status: open -> closed ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue46871] Lambda can't be pickled with "spawn" and only "fork"

Kyle Smith added the comment: I think that's fair, thanks for the conversation at least. I understand python mp a little bit more now... -- status: pending -> open ___ Python tracker

[issue46871] Lambda can't be pickled with "spawn" and only "fork"

Steven D'Aprano added the comment: Oops, replying by email reopens the ticket. Back to pending you go! -- status: open -> pending ___ Python tracker ___

[issue46871] Lambda can't be pickled with "spawn" and only "fork"

Steven D'Aprano added the comment: > The "spawn" method requires pickling the data and callable passed to > the child proces, and that's not supported for lambda's. Ah, today I learned something. Kyle, looks like you were right about it being due to the lambdas. -- status: pending

[issue46871] Lambda can't be pickled with "spawn" and only "fork"

Ronald Oussoren added the comment: This is not a bug in CPython, at best this can be a feature request to make it possible to pickle lambda's (which IMHO is unlikely to happen). The "fork" and "spawn" start methods result in different behaviour in how data is copied into the new worker

[issue46871] Lambda can't be pickled with "spawn" and only "fork"

Ronald Oussoren added the comment: The default start method for multirprocessing was changed from "fork" to "spawn" on macOS. This was done because the "fork" method can easily be triggered into causing hard crashes (on macOS), in particular when the parent proces has called higher-level

[issue46871] Lambda can't be pickled with "spawn" and only "fork"

Change by Kyle Smith : -- title: BaseManager.register no longer supports lambda callable 3.8.12+ -> Lambda can't be pickled with "spawn" and only "fork" ___ Python tracker