Python 多进程应用示例

python中threading模块详解（一）
http://blog.chinaunix.net/uid-27571599-id-3484048.html


import multiprocessing
import time

def func(name):
    outputline=name
    for i in range(3):
        outputline+= " repeat "+str(i)
        time.sleep(1)
    return outputline

def main():
    pool=multiprocessing.Pool(processes=4)
    result=[]
    for i in range(4):
        pname="cpu_%d"%i
        result.append(pool.apply_async(func, (pname, )))
    pool.close()
    pool.join()
    for res in result:
        print res.get()
    print "all processes done"

if __name__ == '__main__':
    main()

   
示例2，使用锁同步

import multiprocessing
import time

def func(name,lock):
    outputline=name
    for i in range(3):
        outputline+= " repeat "+str(i)
        lock.acquire()
        print name+" repeat "+str(i)
        lock.release()
        time.sleep(1)
    return outputline

def main():
    lock=multiprocessing.Lock()
    subprocesses=[]
    for i in range(4):
        pname="cpu_%d"%i
        process=multiprocessing.Process(target=func, args=(pname,lock))
        process.start()
        subprocesses.append(process)
    
    for p in subprocesses:
        p.join()

    print "all processes done"

if __name__ == '__main__':
    main()