Question

我试图在进程中排队列表（在下面名为proc的函数中），然后在我调用event.set()后让进程自行终止。我的函数proc总是完成，从打印输出来判断，但过程本身仍在继续。如果我在调用put较低（batchperq变量）（或每个嵌套列表的大小较小）中排队列表的数量，我可以使这个工作。

import multiprocessing as mp
import queue
import numpy as np
import time

def main():
    trainbatch_q = mp.Queue(10)

    batchperq = 50  
    event = mp.Event()

    tl1 = mp.Process(target=proc,
                            args=( trainbatch_q, 20, batchperq, event))
    tl1.start()
    time.sleep(3)
    event.set()
    tl1.join()
    print("Never printed..")    

def proc(batch_q, batch_size, batchperentry, the_event):
    nrow = 100000 
    i0 = 0
    to_q = []
    while i0 < nrow:
        rowend = min(i0 + batch_size,nrow)
        somerows = np.random.randint(0,5,(rowend-i0,2))
        to_q.append(somerows.tolist())  
        if len(to_q) == batchperentry:
            print("adding..", i0, len(to_q))
            while not the_event.is_set():
                try: 
                    batch_q.put(to_q, block=False)
                    to_q = []
                    break
                except queue.Full:
                    time.sleep(1)
        i0 += batch_size                    
    print("proc finishes")

当我做键盘中断时，我得到了下面的描述......＆＃34;锁定＆＃34;它试图收购吗？与队列有什么关系？

Traceback (most recent call last):
  File "/software/Anaconda3-5.0.0.1-el7-x86_64/lib/python3.6/multiprocessing/process.py", line 252, in _bootstrap
    util._exit_function()
  File "/software/Anaconda3-5.0.0.1-el7-x86_64/lib/python3.6/multiprocessing/util.py", line 322, in _exit_function
    _run_finalizers()
  File "/software/Anaconda3-5.0.0.1-el7-x86_64/lib/python3.6/multiprocessing/util.py", line 262, in _run_finalizers
    finalizer()
  File "/software/Anaconda3-5.0.0.1-el7-x86_64/lib/python3.6/multiprocessing/util.py", line 186, in __call__
    res = self._callback(*self._args, **self._kwargs)
  File "/software/Anaconda3-5.0.0.1-el7-x86_64/lib/python3.6/multiprocessing/queues.py", line 198, in _finalize_join
    thread.join()
  File "/software/Anaconda3-5.0.0.1-el7-x86_64/lib/python3.6/threading.py", line 1056, in join
    self._wait_for_tstate_lock()
  File "/software/Anaconda3-5.0.0.1-el7-x86_64/lib/python3.6/threading.py", line 1072, in _wait_for_tstate_lock
    elif lock.acquire(block, timeout):
KeyboardInterrupt

Answer 1

您的流程永不退出的原因是因为您永远不会告诉它退出。我在您的函数末尾添加了return，您的流程现在似乎正确退出。

def proc(batch_q, batch_size, batchperentry, the_event):
    nrow = 100000
    i0 = 0
    to_q = []
    while i0 < nrow:
        rowend = min(i0 + batch_size,nrow)
        somerows = np.random.randint(0,5,(rowend-i0,2))
        to_q.append(somerows.tolist())  
        if len(to_q) == batchperentry:
            print("adding..", i0, len(to_q))
            while not the_event.is_set():
                try: 
                    batch_q.put(to_q, block=False)
                    to_q = []
                    break
                except queue.Full:
                    time.sleep(1)
        i0 += batch_size                    
    print("proc finishes")
    return            # Added this line, You can have it return whatever is most relevant to you.

这是我运行的完整程序，包括我的更改，以使其成功退出。

import multiprocessing as mp
import queue
import numpy as np
import random
import time

def main():
    trainbatch_q = mp.Queue(10)
    batchperq = 50  
    event = mp.Event()

    tl1 = mp.Process(target=proc,
                            args=( trainbatch_q, 20, batchperq, event))
    print("Starting")
    tl1.start()
    time.sleep(3)
    event.set()
    tl1.join()
    print("Never printed..")    

def proc(batch_q, batch_size, batchperentry, the_event):
    nrow = 100000
    i0 = 0
    to_q = []
    while i0 < nrow:
        rowend = min(i0 + batch_size,nrow)
        somerows = np.random.randint(0,5,(rowend-i0,2))
        to_q.append(somerows.tolist())  
        if len(to_q) == batchperentry:
            print("adding..", i0, len(to_q))
            while not the_event.is_set():
                try: 
                    batch_q.put(to_q, block=False)
                    to_q = []
                    break
                except queue.Full:
                    time.sleep(1)
        i0 += batch_size                    
    print("proc finishes")
    return      # Added this line, You can have it return whatever is most relevant to you.

if __name__ == "__main__":
  main()

希望这有帮助。

多处理队列存储列表列表

1 个答案: