As far as I know does the sleep command put the process into "sleep/disable" mode and awake it after the given timeframe. This means there is no waste of CPU cycles during the sleep. The only waste is the real program doing `while` and script1.sh Cheers, Simon >-----Original Message----- >From: redhat-list-bounces@xxxxxxxxxx >[mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of Geofrey Rainey >Sent: Monday, April 20, 2009 10:06 PM >To: General Red Hat Linux discussion list >Subject: RE: Crontab > >There's a condition known as busy waiting whereby a process >Loops continuously wasting CPU cycles as opposed to the process >Going into a wait state. >I wonder if sleeping a process wastes CPU cycles as described and >if so is there a better implentation of this? > > >-----Original Message----- >From: redhat-list-bounces@xxxxxxxxxx >[mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of Reber, Simon >Sent: Monday, 20 April 2009 9:07 p.m. >To: General Red Hat Linux discussion list >Subject: RE: Crontab > >Instead of doing this, >Simply build a script that has a content as follow: > >while [ true ] > do > script1.sh > sleep 30 >done > >It's much simpler and you don't need to run it via cron every minute. > But you still can control the script and the start/stop via >cron. > >Cheers, >Simon > >>-----Original Message----- >>From: redhat-list-bounces@xxxxxxxxxx >>[mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of Rohit khaladkar >>Sent: Monday, April 20, 2009 10:59 AM >>To: General Red Hat Linux discussion list >>Subject: Re: Crontab >> >>I guess you cannot have crontab entry in terms of seconds.But you can >>create a script which would repeatedly run your script and give an >>interval of 30 seconds. >>For eg, create a tmp.sh script which would run your desired >script (say >>script1.sh) after every 30 seconds. >> >>Your tmp.sh script would look like >> >>#!/bin/sh >>script1.sh >>sleep 30 >>script1.sh >>sleep 30 >>script1.sh >> >> >>Make an entry in the crontab to execute this script every minute. >> >>This should solve the purpose. If anyone comes up with a better idea, >>feel free to go ahead with that, but this is a workaround, if you are >>stuck. >> >>Thanks! >>Rohit Khaladkar. >> >>On Mon, Apr 20, 2009 at 2:17 PM, ~~~0Pen ~~~ S0uRce ~~~ >><vijay1313@xxxxxxxxx >>> wrote: >> >>> Hi guys, >>> Do any one have idea that how can i >>configure crontab >>> to run a script after every 30 seconds,i know about default >>parameters of >>> crontab and tried google also,but could not find any thing. >>> >>> Any suggestion Please !!!! >>> >>> >>> >>> -- >>> ~~~ 0Pen ~~~ S0uRce ~~~ >>> -- >>> redhat-list mailing list >>> unsubscribe >mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe >>> https://www.redhat.com/mailman/listinfo/redhat-list >>> >>-- >>redhat-list mailing list >>unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe >>https://www.redhat.com/mailman/listinfo/redhat-list >> > >-- >redhat-list mailing list >unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe >https://www.redhat.com/mailman/listinfo/redhat-list >========================================================== >For more information on the Television New Zealand Group, visit us >online at tvnz.co.nz >========================================================== >CAUTION: This e-mail and any attachment(s) contain information that >is intended to be read only by the named recipient(s). This >information >is not to be used or stored by any other person and/or organisation. > > >-- >redhat-list mailing list >unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe >https://www.redhat.com/mailman/listinfo/redhat-list > -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
