topic renice via cron in Operating System - Linux

renice via cron

K.C. Chan — Thu, 26 Dec 2002 20:12:20 GMT

All, I am having problem setting priority of a process to a higher value via cron job. According to the man page on renice, only root can up the priority of a process. How would I get around this? Thanks.

Re: renice via cron

Szilveszter Juhos — Fri, 27 Dec 2002 00:27:20 GMT

Use sudo in crontab to change the priority. It is something like i) with visudo include cron into the sudoers file with NOPASSWD and only for the renice command ii) edit the script that is called in the crontab like:

sudo renice +1

Cheers
Szilva

Re: renice via cron

K.C. Chan — Fri, 27 Dec 2002 01:08:24 GMT

I know sudo will work, does any one know of anthing else? I will use sudo as the last resort. Thanks.

Re: renice via cron

Szilveszter Juhos — Fri, 27 Dec 2002 21:46:06 GMT

http://freshmeat.net/projects/super/?topic_id=136
Hm?
Szilva

Re: renice via cron

Rory R Hammond — Mon, 30 Dec 2002 17:02:33 GMT

We have 2 programs xmgen and cscomm that our developer has failed to startup up with a nice value. I created a root cron job containing the following lines and ran it Once an hour until the developer fixed the problem.
(this was using HPUX 11i.) You might have change the cut fields for other unixes.

good luck
Rory

for arg in `ps -fel |grep -e xmgen -e cscomm |grep -v grep|cut -c 15-21`
do
renice -n +20 ${arg}
done

Re: renice via cron

K.C. Chan — Mon, 30 Dec 2002 17:26:17 GMT

All,
I've tried running the cron job under root. But still the priority did not increase. Any idea?

Re: renice via cron

U.SivaKumar_2 — Tue, 31 Dec 2002 06:45:08 GMT

Hi,

Does the priority Increases when you run the command as root in the shell prompt manually ?

Try this in that Cron script

/usr/bin/snice -20

eg:

/usr/sbin/snice -20 httpd

regards,
U.SivaKumar

Re: renice via cron

U.SivaKumar_2 — Tue, 31 Dec 2002 06:54:17 GMT

Hi,

Are you running that process as what ? root or that user ?.

regards,
U.SivaKumar

Re: renice via cron

K.C. Chan — Tue, 31 Dec 2002 14:38:07 GMT

SivaKimar,
Yes when I ran it manually it works. Yes, I am running the cron job as root. Yes, I've included the full path of the command as /usr/bin/renice -19 . Any ideas why? Thanks.

Re: renice via cron

K.C. Chan — Tue, 31 Dec 2002 16:16:00 GMT

ALL,
I've figured it out; There was no problem running renicing priority as root via cron. It was ths script, it was checking against an environmental varialbe USER to see if root is running the script. Unfortunately this was not set in cron, this is solved when I set the USER variable in cron. Thanks all for your help.