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Old 11-17-2009, 01:01 PM   #1
your_shadow03
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cronjob to run every 15 minutes?


Hello,

Can anyone help me setting up cronjob to run every 30 seconds.
Shall this entry help me:

Code:
*/2 * * * *
Pls suggest?
 
Old 11-17-2009, 01:05 PM   #2
pljvaldez
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http://en.wikipedia.org/wiki/Cron
 
Old 11-17-2009, 01:05 PM   #3
EricTRA
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Hi,

If I'm not mistaking the minimum time unit for cron is one minute, no less. The entry you posted means every two minutes (dividable by 2). If you put only the * it will run every minute.

Kind regards,

Eric
 
Old 11-17-2009, 01:08 PM   #4
indiajoe
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Hi
I don't think you can run crontab in an interval less than 1 minute.
But if you want to do it in 30 second, just make that in the script you are calling.
To run crontab in every 15 mins, following line will do
Code:
*/15 * * * * Command
Just google for crontab examples.
-Cheers
indiajoe

Last edited by indiajoe; 11-17-2009 at 01:10 PM.
 
Old 11-17-2009, 05:14 PM   #5
chrism01
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Can you clarify whether you mean every 15 mins or every 30 seconds?
The minimum time accuracy in cron is 1 minute.
It's inefficient to go that low for frequency though, as cron has to instantiate a whole new process environment every time.
My rule of thumb is that for anything more frequent than every 5 mins, just write a daemon that sleeps as long as required at the start of each iteration. Much more efficient.
 
Old 11-19-2009, 10:58 PM   #6
your_shadow03
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Sorry for the late response.
I want to run every 30 seconds.
 
  


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