python多线程和多进程对比

1、多线程：开启一个进程test.py ,占用两个cpu  共占用45%左右(top -c ,按1)  多进程：开启两个进程test.py 用两个cpu  90%*2左右

test.py 

# coding=utf-8

from multiprocessing import Pool  # 多线程版本from multiprocessing.dummy import Pool 
import sys, os 
import time

def timetask(times):
    while 1:
        pass

    
if __name__ == '__main__':
    startTime = time.time()
    worknum = 2  
    processnum = 2 
    pool = Pool(processnum)  
    for i in range(worknum):
        pool.apply_async(timetask, (i, ))  
    pool.close()
    pool.join()
    endTime = time.time()
    print "time :", endTime - startTime

2、多线程：开启一个进程test.py ,两个gzip进程 占用两个cpu  多进程：开启两个进程test.py  ,两个gzip进程 (主进程test.py  S状态)

多线程、多进程都用两个cpu  90%左右

# coding=utf-8

from multiprocessing import Pool 
import sys, os
import time

def timetask(times):
    cmd="tar zcfPh /nerri_%s.tar.gz   /tmp"   % times
    os.system(cmd)


    
if __name__ == '__main__':
    startTime = time.time()
    worknum = 2  # time : 55.9383509159
    processnum = 2 # 进程版本 processnum:2, time : 55.9383509159;processnum:1,time : 108.528738976 ;线程版本 processnum:2,time : 55.0623002052 
    pool = Pool(processnum)  
    for i in range(worknum):
        pool.apply_async(timetask, (i, ))  
    pool.close()
    pool.join()
    endTime = time.time()
    print "time :", endTime - startTime