Question

在使用模块multiprocessing时，如何在Python中使一个线程休眠而不使其他线程休眠？当队列少于10个元素时，我想使getDataProcess休眠一段时间。在这段时间内，主线程将用更多数据填充队列，而while循环将继续执行。

import multiprocessing as mp
import os
import csv
import sys
import subprocess
import time
cur=[]
dataList=[]
def getData(queue):
    global dataList
    print('get data started')
    with open('temp.csv','w+') as file:
        writer=csv.DictWriter(file,fieldnames=['index','name','fileaccess'],lineterminator='\n')
        while not queue.empty():
            cur=queue.get()
            writer.writerow(cur)
            if len(dataList)<=100:
                dataList.append(cur)
                print('appending to datalist',end='\r')
            if len(dataList)==100:
                showData(queue)
            if(queue.qsize()<10):
                print('danger race condition'+str(queue.qsize()))
                if os.path.exists('temp.csv'):
                    try:
                        os.rename('temp.csv','temp.csv')
                        print('may have completed reading')
                    except OSError as e:
                        #time.sleep(10)
                        print('sleeping to prevent end ')

def showData(queue):
    print('showdata started')
    global dataList

    #time.sleep(1)

    print(dataList)
    if(queue.qsize()<100):
        print('danger race condition')
if __name__=="__main__":
    try:
        filename=sys.argv[1]
        key=sys.argv[2]
    except:
        print('arguments not provided')
    queue = mp.Queue() 
    getDataProcess=mp.Process(target=getData,args=(queue,))
    getDataProcessStatus=False
    showDataProcess=mp.Process(target=showData,args=(queue,))
    showDataProcessStatus=False
    with open('archive/data.csv') as file:
        matches=0
        reader=csv.DictReader(file,fieldnames=['index','name','fileaccess'],delimiter=',')
        header=next(reader)
        for i,row in enumerate(reader):
            if(row['fileaccess'][0]=='d'):
                matches+=1
                queue.put(row)
                if(getDataProcessStatus==False):
                        getDataProcess.start()
                        getDataProcessStatus=True
                        print('getdata started')
                # if(matches>200):
                #     if(showDataProcessStatus==False):
                #         print('show data started')
                #         showDataProcess.start()
                #         showDataProcessStatus=True

Answer 1

使用：

time.sleep( delay )

这将使您的进程进入睡眠状态而不会影响其他人。

如何使进程休眠而不使其他进程在python multiprocessing中休眠

1 个答案: