From owner-freebsd-hackers  Tue Apr 11  9:38:58 2000
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Date: Tue, 11 Apr 2000 12:56:43 +0200
From: Bjoern Fischer <bfischer@Techfak.Uni-Bielefeld.DE>
Subject: Re: efficiency of maxproc hardlimit
In-reply-to: <20000410013139.R4381@fw.wintelcom.net>; from bright@wintelcom.net
 on Mon, Apr 10, 2000 at 01:31:39AM -0700
To: Alfred Perlstein <bright@wintelcom.net>
Cc: freebsd-hackers@FreeBSD.ORG
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On Mon, Apr 10, 2000 at 01:31:39AM -0700, Alfred Perlstein wrote:
[...]
> >   main(){fork();main();}
> >=20
> > leaves the machine in an unusable state (it does ping
> > back, one may break into the kernel debugger, but no
> > io).
> >=20
> > Any way to prevent this (without harming the user)?
>=20
> Please reread the documentation on limits.
>=20
> cputime         unlimited
> filesize        unlimited
> datasize        256MB       <-
> stacksize       64MB        <-
> coredumpsize    unlimited
> memoryuse       unlimited
> memorylocked    unlimited
> maxproc         4115
> descriptors     8232
> sockbufsize     unlimited
>=20
> If appropriate limits are in place and you still get problems
> then let us know.

Already set:

  ...
  datasize          1048576 kb
  stacksize-cur       16384 kb
  ...

Some more information: This happens on a diskless client (265MB RAM,
lots of swap (1.2G) on the server). When I limit the stacksize to 3MB,
all fork-processes fit into RAM and the situation is recoverable
with some effort and `/usr/bin/killall' (Eww, that's a perl script).

With a stacksize limit of 16M 64 fork processes sould easily fit
into swap, so I don't think it is an out-of-swap situation.

Listening to the ether on the server, I realized heavy RPC traffic
(swapping, probably) and then silence. Any idea how to find out,
whether swap in not really full, the client won't answer but maybe
looking for some kind of NFS write errors or something?

As this is a strange setup (1.2G swap via NFS) this issue
in not critical at all.

  Bj=F6rn

--=20
-----BEGIN GEEK CODE BLOCK-----
GCS d--(+) s++: a- C+++(-) UB++++OSI++++$ P+++(-) L---(++) !E W- N+ o>+
K- !w !O !M !V  PS++  PE-  PGP++  t+++  !5 X++ tv- b+++ D++ G e+ h-- y+=20
------END GEEK CODE BLOCK------


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