top delay value
Coleman Kane
zombyfork at gmail.com
Wed Jan 31 21:30:12 UTC 2007
On 1/31/07, Mike Meyer <mwm-keyword-freebsdhackers2.e313df at mired.org> wrote:
>
> In <20070131170241.230960 at gmx.net>, Dr. Markus Waldeck <waldeck at gmx.de>
> 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 at mired.org>
> 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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