On Sat, 10 Apr 1999, Dmitry Valdov wrote:

> 
> 
> On Sat, 10 Apr 1999, Chris Costello wrote:
> 
> > Date: Sat, 10 Apr 1999 02:05:33 -0500
> > From: Chris Costello <ch...@holly.dyndns.org>
> > Reply-To: ch...@calldei.com
> > To: Dmitry Valdov <d...@dv.ru>
> > Cc: freebsd-current@FreeBSD.ORG, freebsd-questi...@freebsd.org
> > Subject: Re: DoS from local users (fwd)
> > 
> > On Sat, Apr 10, 1999, Dmitry Valdov wrote:
> > > >    You typically want to set a restriction as to how many
> > > > processes a user can spawn.  This is done by editing
> > > > /etc/login.conf and changing the user's login class, see the man
> > > > page for 'login.conf'.
> > > > 
> > > 
> > > I'm about CPU usage, not about many processes.
> > > See:
> > > CPU states: 17.8% user,  0.0% nice, 81.7% system,  0.5% interrupt,  0.0%
> > > idle 
> > > on any (tested on P2-45) machine.
> > > 
> > > CPU is used by SYSTEM, not by USER. So I can't restrict it with login.conf
> > > And load average can be up to 20-40 :( 
> > > 
> > > Please don't redirect me to -questions, it's a kernel problem, not just
> > > config. 
> > 
> >    How is it a kernel problem?  It's a forkbomb.  It spawns many
> > processes.  You can also limit CPU usage with login.conf, I
> > believe.
> 
> Hmm. How I can limit CPU usage by SYSTEM? See top's output below.
> 
> Dmitry.
> 
> PS. I've just tried it. And I'm right - CPU usage limit can't help.
> 

So? Processes that run a while go down in priority [McKusick95 I believe, THE
book] so they are preempted easily. Look in top and see if they're all at
the top of the list. I bet they're not! Also, you can set per-user niceness
levels, and why are you being so liberal giving a standard LUSER 32 processes?
This is a system administration problem.

> 
> 
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 Brian Feldman                _ __ ___ ____  ___ ___ ___  
 gr...@unixhelp.org                _ __ ___ | _ ) __|   \ 
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