Re: deschall harmful to Irix?

Darrell Kindred (dkindred@cmu.edu)
Sat, 31 May 1997 12:19:39 -0400


Jonas Schlein writes:
> I'm running deschall nohup'ed in the background with this syntax. My
> actual command line is:
>
> nohup npri -h 150 deschall keymaster.verser.frii.com > /dev/null 2>&1 &
>
> On the IRIX multiuser system I attempted this one, expecting to be
> preemted most of the time, I get the following from 'top':
>
> user pid pgrp %cpu proc pri size rss time command
> schlein 23588 23588 93.39 * b150 309 35 799:54 deschall-irix6.
>
> My process is always at the top of 'top' if you catch my drift. Am I
> doing this wrong or is everyone else just not running anything intensive
> when I'm doing my checks?

No, you're doing it right--there are probably no other
cpu-intensive processes running at the moment, so deschall
is using the cpu when it would otherwise be idle.

A simple way to demonstrate this (to yourself or to folks
who are concerned about your deschall process) is to run
a cpu-intensive task, like

sh -c 'while : ; do : ; done'

Then, run 'top' in another window, and watch the sh
process get 99% of the CPU and deschall drop to near zero.
(If your machine has multiple CPUs, run several of the
spinning processes.)

Don't forget to kill the spinning process after you're done with
the demonstration! :)

- Darrell