Python how to do multiprocessing inside of a class?

Question

I have a code structure that looks like this:

Class A:
  def __init__(self):
    processes = []
    for i in range(1000):
      p = Process(target=self.RunProces         


        

Answer 1

A practical work-around is to break down your class, e.g. like this:

class A:
    def __init__(self, ...):
        pass

    def compute(self):
        procs = [Process(self.run, ...) for ... in ...]
        [p.start() for p in procs]
        [p.join() for p in procs]

    def run(self, ...):
        pass

pool = A(...)
pool.compute()

When you fork a process inside __init__, the class instance self may not be fully initialised anyway, thus it's odd to ask a subprocess to execute self.run, although technically, yes, it's possible.

If it's not that, then it sounds like an instance of this issue:

http://bugs.python.org/issue11240