Question

我写了一个Python类来并行绘制pylot。它在Linux上工作正常，但是当我在Windows上尝试时遇到了问题。甚至走到我都无法腌制单个字符串的程度。我总是最终会收到此错误：

Traceback (most recent call last):
  File "test.py", line 50, in <module>
    test()
  File "test.py", line 7, in test
    asyncPlotter.saveLinePlotVec3("test")
  File "test.py", line 41, in saveLinePlotVec3
    args=(test, ))
  File "test.py", line 34, in process
    p.start()
  File "C:\Users\adrian\AppData\Local\Programs\Python\Python37\lib\multiprocessing\process.py", line 112, in start
    self._popen = self._Popen(self)
  File "C:\Users\adrian\AppData\Local\Programs\Python\Python37\lib\multiprocessing\context.py", line 223, in _Popen
    return _default_context.get_context().Process._Popen(process_obj)
  File "C:\Users\adrian\AppData\Local\Programs\Python\Python37\lib\multiprocessing\context.py", line 322, in _Popen
    return Popen(process_obj)
  File "C:\Users\adrian\AppData\Local\Programs\Python\Python37\lib\multiprocessing\popen_spawn_win32.py", line 89, in __init__
    reduction.dump(process_obj, to_child)
  File "C:\Users\adrian\AppData\Local\Programs\Python\Python37\lib\multiprocessing\reduction.py", line 60, in dump
    ForkingPickler(file, protocol).dump(obj)
TypeError: can't pickle weakref objects

C:\Python\MonteCarloTools>Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "C:\Users\adrian\AppData\Local\Programs\Python\Python37\lib\multiprocessing\spawn.py", line 99, in spawn_main
    new_handle = reduction.steal_handle(parent_pid, pipe_handle)
  File "C:\Users\adrian\AppData\Local\Programs\Python\Python37\lib\multiprocessing\reduction.py", line 82, in steal_handle
    _winapi.PROCESS_DUP_HANDLE, False, source_pid)
OSError: [WinError 87] The parameter is incorrect

我将其范围缩小为Windows使用的生成启动方法（https://docs.python.org/3/library/multiprocessing.html#contexts-and-start-methods），当我在Linux上使用相同的启动方法时，可以重现该错误。

import multiprocessing as mp
def test():

    asyncPlotter = AsyncPlotter()

    asyncPlotter.saveLinePlotVec3("test")

    asyncPlotter.saveLinePlotVec3("test")

    asyncPlotter.saveLinePlotVec3("test")

    asyncPlotter.join()


class AsyncPlotter():

    def __init__(self, processes=mp.cpu_count()):

        self.manager = mp.Manager()
        self.nc = self.manager.Value('i', 0)
        self.pids = []
        self.processes = processes


    def linePlotVec3(self, nc, processes, test):

        self.waitOnPool(nc, processes)

        return None


    def waitOnPool(self, nc, processes):

        while nc.value >= processes:
            time.sleep(0.1)
        nc.value += 1


    def process(self, target, args):

        p = mp.Process(target=target, args=args)
        p.start()
        self.pids.append(p)


    def saveLinePlotVec3(self, test):

        self.process(target=self.linePlotVec3,
                       args=(self.nc, self.processes, test))


    def join(self):
        for p in self.pids:
            p.join()


if __name__=='__main__':
    test()

我希望我也可以在Windows上使用此方法来腌制任何类型的字符串，列表，字典等。如果有人能找到一种在Windows上实现此功能的方法，我将不胜感激。谢谢！

Answer 1

更改

self.process(target=self.linePlotVec3, args=(test, ))

到

self.process(target=AsyncPlotter.linePlotVec3, args=(test, ))

Process接受类或全局方法，因此当您尝试将其传递给实例方法时会崩溃

Python多重处理Process（）在Windows 10上不起作用（即使用于腌制简单的字符串）

1 个答案: