Re: top delay value

On 1/31/07, Mike Meyer <mwm-keyword-freebsdhackers2.e313df@xxxxxxxxx> wrote:

In <20070131170241.230960@xxxxxxx>, Dr. Markus Waldeck <waldeck@xxxxxx>
typed:
> > > > typing "while :; do :; done". There are a thousand ways
>
> > No. What I write above is not a "fork bomb", it's a single
> > process which is wasting CPU in a busy loop. It's exactly
> > equivalent to top(1) with zero delay, except that top
> > produces some output, while a busy loop does nothing useful
> > at all.
>
> I tested different shells and I found out that an exlicit sub shell
> is required to let the shell fork:
>
> while :; do (:); done

That's still not a fork bomb. While it creates a process every time
through the loop, the process exits before the loop continues, so
you've still got just a few processes. Basicaly, it's still a busy
loop.

A true fork bomb creates an ever-increasing number of processes,
typically by forking copies of itself (which led to them being called
"rabbit jobs" when I first ran into one).

<mike
--
Mike Meyer <mwm@xxxxxxxxx>
http://www.mired.org/consulting.html
Independent Network/Unix/Perforce consultant, email for more information.


Don't forget that a real fork bomb would fork forking forkers thereby
growing the process overhead and time exponentially!

e.g:
perl -e 'while(1) { fork; };'

--
Coleman Kane
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