No threading.start_new_thread(), useful addition?

Ethan Furman ethan at
Sat Oct 10 00:57:52 CEST 2009

Christian Heimes wrote:
> Laszlo Nagy wrote:
>>IMHO it is much cleaner to implement this as a decorator. Pro: 
>>transparent passing of positional and keyword arguments, keeps function 
> You are entitled to your opinion but I STRONGLY recommend against your
> decorator. You MUST NOT start threads a a side effect of a module
> import. It can lead to severe bugs and dead lock the entire interpreter.
> I'm speaking as an experienced Python developer and a CPython core
> developer. Please trust me in this. The interaction between the import
> system, its global import lock and threads can and will lead to
> surprising and hard to debug bugs. A well designed application loads its
> modules first and then initializes its components explicitly. You don't
> want to fire up threads randomly!
> Christian

Okay, I for one will never start threads as a side-effect of module import.

Other than that, are there other inherent problems with using that 
decorator at non-import times?


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