Python performs the same task non-blocking mode every 1s

First we use crontab every 1 minutes to perform, look at the effect, and then in doing this,

Configure Crontab

[Email protected] ~]# crontab-l

*/1 * * * * Ping www.baidu.com >/dev/nul

Note that I deliberately wrote such an order to always ping, the purpose is when entering the next minute, the system will automatically open another process to execute, in order to see the effect

By looking at the Crontab log, we can see that two

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Because this command will always ping, so when you look at the PS-EF, there will be two

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Next we test the script we wrote every 1s, to see whether the same effect as crontab

The script content is as follows

Import threading

Import Time,os

def run ():

Os.system (' ping www.baidu.com >/dev/nul ')

I=0

While i<3:

I+=1

Print "Start", Time.strftime ("%y-%m-%d_%h-%m-%s")

t = Threading. Thread (target=run,args= ())

T.start ()

Time.sleep (1)

Print "End", Time.strftime ("%y-%m-%d_%h-%m-%s")

As a result of testing I have limited to 3 times, easy to see the effect, if you want to continue to change to while true

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From can be seen every 1s execution, altogether performed 3 times,

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This article is from the "Server" blog, so be sure to keep this source http://zhangfang2012.blog.51cto.com/6380212/1579172

Python performs the same task non-blocking mode every 1s