[Python-ideas] Concurrency Modules

[Sven R. Kunze]

Hi,

that's a follow up on the discussion started on python-dev ('The 
importance of the async keyword') and this issue 
http://bugs.python.org/issue24571 .

After discussing the whole topic and reading it up further, it became 
clear to me what's actually missing in Python. That is a definitive 
guide of why/when a certain concurrency module is supposed to be used:

Currently, I can name 4 modules of which I know that they more or less 
deal with the topic:
  - concurrent
  - threading
  - asyncio
  - multiprocessing

In order to make a sound decision for the question: "Which one(s) do I 
use?", at least the following items should be somehow defined clearly 
for these modules:

1) relationship between the modules
2) NON-overlapping usage scenarios
3) future development intentions
4) ease of usage of the modules => future syntax
5) examples


Remarks to the items:

1)
For the basic understanding
Do they complement each other?
Differences in behavior?
Do they overlap from the perspective of the programmer?
They mostly do not care about internal details; they need to get things 
done (threads <-> processes) as long as the result is the same.

2) Extremely important to make the decision fast

3)
Will asyncio incorporate all concepts of the other modules in a seamless 
way?
Or are they just complementary?

4) Closely related to 3)

5) Maybe in close correlation with 2) and 1)

Cheers,
Chuck