在python中实现此工作流的最佳方法

2024-06-12 19:02:46 发布

您现在位置:Python中文网/ 问答频道 /正文

我想用Python实现以下工作流。在这个例子中,我有5个进程在运行平行。一过程被定义为经理,而其他人都是工人。经理以循环方式多次执行控制例行程序,直到所有工人停止。在

关于这个问题的主要观点是,每个工人从一个不同的工作清单开始。然而,当他们在处理他们的工作时,他们会将更多的工作添加到自己的列表中,并且在某些情况下,重复工作的情况会发生在工人身上。经理的职责是避免重复工作。在

Workflow overview

我目前正在尝试使用Python多处理和管道来实现这一点。下面是我的代码,用于对通信进行测试:

import multiprocessing as mp
import time
import random


def checkManager(i, data_pipe, com_pipe, work_list):
    com_out, com_in  = com_pipe
    if com_out.poll():  ##check if there is anything to read
        msg = com_out.recv()
        print i, " received message ", msg
        if msg == "SEND":
            data_out, data_in = data_pipe
            data_in.send(work_list)
            work_list = com_out.recv()
    return work_list

def myfunc(i, data_pipe, com_pipe, work_list):
    print "starting worker ", i, " with list: ", work_list
    while work_list != []:
        time.sleep(3) ##sleep just to simulate some work delay
        work_list = checkManager(i, data_pipe, com_pipe, work_list) ##check if manager wants to comunicate
    print "stopping worker ", i


print "Starting..."

data_pipe = mp.Pipe() ##pipe to receive work lists from all workers
pipes = []  ##comunication pipe for each worker
workers = []

##spawn workers
for i in range(0,4):
    pipe = mp.Pipe() ##pipe for comunication for that process
    r = random.randint(10, 100) ##create random list just to test
    p = mp.Process(target=myfunc,args=(i, data_pipe, pipe, range(r)))  ##create process
    pipes.append(pipe)
    workers.append(p)
    p.start()

index = 0
stopped_workers = []
data_out, data_in = data_pipe
while len(stopped_workers) != len(workers):
    time.sleep(2)
    for i in range(0, len(workers)):
        if i in stopped_workers: ##check if wworker has already stopepd
            continue
        r = random.randint(0,100)  ##just to avoid send the request all the times..
        if r > 80:
            print "Comunication with ", i
            output, input = pipes[i]
            input.send("SEND") ## send message
            work_list = data_out.recv() #block untill receive data
            print "data: ", work_list
            input.send([]) ##send an empty list just to test if it stops
            stopped_workers.append(i) ##add to the workers that already stopped

print "Stoping main"

在这个简单的测试中一切都很好,但是我希望这是尽可能有效的,并且有一些东西我不喜欢在我的代码。在

首先,我认为如果我有一个机制,可以向工作进程发送一个信号,而不是让它们不时检查某个函数,那么效率会更高。我试着用信号,但一直没能正常工作。 除此之外,我创建的管道数量与进程数量相同,我不确定这是否是最佳解决方案。我用多处理.池,但这似乎不是解决我问题的好办法。在

最后,使用python MPI库实现所有功能会更好吗?在

提前谢谢


Tags: toincomsendfordataifout