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Blur my cron jobs

Cron jobs that repeat often, e.g. every 5 or 10 minutes, can be easily set up with something like

*/5 *  * * *  $HOME/bin/every5minutes.sh

Though, all of these cron jobs start at the same time intervals. In case of more expensive jobs or a hell of lot of whatever jobs one might want to try to distribute them. One way of doing this is of course

4,9,14,19,24,29,34,39,44,49,54,59 *  * * *  $HOME/bin/every5minutes.sh

Another approach is to sleep some random time before doing the actual job, and some scripts have this built in. On systems using Bash as the main (default/cron) shell one can use bash's built-in variable RANDOM like in

*/5 *  * * *  sleep $((RANDOM * 60 / 32767)) ; $HOME/bin/every5minutes.sh


If you are like me, and you have to put each and everything into a shell script, well, then you will probably call it something like blur and use it as

*/5 *  * * *  blur 60 ; $HOME/bin/every5minutes.sh

Hey, blur.sh comes even with a GPL license ;-)

Note that the cron examples above are for users' crontabs, not root's.

blog/090518_blur_my_cron_jobs.txt · Last modified: 2009-05-18 22:13 by andreas