本文定位:想通过python调用top命令获取cpu使用率但暂时没有思路的情况。
如果单纯为了获得cpu的利用率,通过top命令重定向可以轻松实现,命令如下:
top -bi > cpuHistory.log
或
top -bi | tee cpuHistory.log
这个就不解释了,不懂的朋友查询下top的帮助文档。这里要实现的是通过python调用top命令,并获得cpu的利用率信息。
用过popen的朋友很快就能想到类似如下的代码(这个是我第一次写的代码,*_*):
#! /usr/bin/python
import os,time
time2sleep = 1.5
while True:
print os.popen('top -bi -n 1').read().split('\n')[2]
time.sleep(time2sleep)
原理看起来没错,可是跑起来就出问题了:cpu的idle值一直不变!!!
原因在于执行的命令“top -bi -n 1”:单独执行这个命令,你会发现输出结果中cpu的idle值就是一直不变的。
所以不能这样写……
在终端执行“top -bi -n 2”命令,你会发现第二个值每次都在变化,这个就是我们想要结果。
考虑到时间问题,命令这样写会更好:“top -bi -n 2 -d 0.02”
代码如下:
#! /usr/bin/python
'''
File : cpuRate.py
Author : Mike
E-Mail : Mike_Zhang@live.com
'''
import os,time
time2sleep = 2.5
while True:
print int(time.time()),
print os.popen('top -bi -n 2 -d 0.02').read().split('\n\n\n')[1].split('\n')[2]
time.sleep(time2sleep)
执行效果如下:
$ ./cpuRate.py
1328109437 Cpu(s): 10.0%us, 20.0%sy, 0.0%ni, 70.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
1328109441 Cpu(s): 0.0%us, 16.7%sy, 0.0%ni, 83.3%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
1328109444 Cpu(s): 0.0%us, 16.7%sy, 0.0%ni, 83.3%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
1328109447 Cpu(s): 12.5%us, 12.5%sy, 0.0%ni, 75.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
好,就这些了,希望对你有帮助。

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