misc/131290: How to completely freeze FreeBSD 7.1 under a non-privileged user

[Mikolaj Golub]

On Mon, 2 Feb 2009 12:13:18 -0800 Sergey S wrote:

> Hello.
>
>> Limits can be configured in login.conf for example, else the system will slowly die out of resource exhaustion.
>
> It sounds like you haven't tried to reproduce the bug. Actually it has
> *nothing* to do with resource exhaustion and "slowly dying". Your
> system will die before you can say "knife". Most probably it will
> happen during the first call to escript.erl, but there is a chance
> you'll need to run it a few times (2-3). So to automate it, I've
> written loop.sh.
>
> It isn't necessary to use loop.sh. Just run escript.erl (which doesn't
> contain any memory/CPU consuming calls).
>
>> This is not a PR nor a bug.
>
> Just try it.

Sergey,

I have tried your scripts and have not managed to reproduce the hang, even
running the loop script without sleep.

If you want to draw developer's' attention to your problem, you need to
do some investigation and provide more info. If the system deadlocks you can
try to get useful information following the steps described in FreeBSD
Developers' Handbook.

http://www.freebsd.org/doc/en_US.ISO8859-1/books/developers-handbook/kerneldebug-deadlocks.html

But I would recommend you to start from simpler techniques, e.g. running in
parallel top and other system utilities and writing the output to the file for
further investigation. Something like this:

top -b -s1 -S -d1000 1000 > top.output &
./gistfile1.sh

-- 
Mikolaj Golub