From owner-freebsd-net  Wed Oct 10  8:46:55 2001
Delivered-To: freebsd-net@freebsd.org
Received: from wall.polstra.com (wall-gw.polstra.com [206.213.73.130])
	by hub.freebsd.org (Postfix) with ESMTP id 65C1237B405
	for <net@freebsd.org>; Wed, 10 Oct 2001 08:46:46 -0700 (PDT)
Received: from vashon.polstra.com (vashon.polstra.com [206.213.73.13])
	by wall.polstra.com (8.11.3/8.11.3) with ESMTP id f9AFkd805323;
	Wed, 10 Oct 2001 08:46:39 -0700 (PDT)
	(envelope-from jdp@wall.polstra.com)
Received: (from jdp@localhost)
	by vashon.polstra.com (8.11.6/8.11.0) id f9AFkcd86407;
	Wed, 10 Oct 2001 08:46:38 -0700 (PDT)
	(envelope-from jdp)
Date: Wed, 10 Oct 2001 08:46:38 -0700 (PDT)
Message-Id: <200110101546.f9AFkcd86407@vashon.polstra.com>
To: net@freebsd.org
From: John Polstra <jdp@polstra.com>
Cc: le@cs.unc.edu
Subject: Re: Connect(2) problem
In-Reply-To: <Pine.LNX.4.32.0110091654450.959-100000@le-cs.cs.unc.edu>
References: <Pine.LNX.4.32.0110091654450.959-100000@le-cs.cs.unc.edu>
Organization: Polstra & Co., Seattle, WA
Sender: owner-freebsd-net@FreeBSD.ORG
Precedence: bulk
List-ID: <freebsd-net.FreeBSD.ORG>
List-Archive: <http://docs.freebsd.org/mail/> (Web Archive)
List-Help: <mailto:majordomo@FreeBSD.ORG?subject=help> (List Instructions)
List-Subscribe: <mailto:majordomo@FreeBSD.ORG?subject=subscribe%20freebsd-net>
List-Unsubscribe: <mailto:majordomo@FreeBSD.ORG?subject=unsubscribe%20freebsd-net>
X-Loop: FreeBSD.org

In article <Pine.LNX.4.32.0110091654450.959-100000@le-cs.cs.unc.edu>,
Nguyen-Tuong Long Le  <le@cs.unc.edu> wrote:
> 
> I have a software that simulates web clients and servers to create
> network congestion (for the purpose of doing research in network
> congestion). In our experiment, a client opens an HTTP connection
> to a server, fetches a number of objects, and then closes the
> connection. A problem I seem to have right now is that a client
> machine cannot simulate more than 3000 connections. When my client
> machine simulates more than 3000 connections, it's able to open
> a socket but then connect(2) fails with errno 35 (Resource
> temporarily unavailable). Another interesting notice is that the
> connect(2) system call blocks for a few miliseconds before it
> fails although fcntl(2) was used to make the socket non-blocking.
> The OS version I am using is FreeBSD 4.3-release.

In addition to the suggestion from Alex Rousskov, adding these lines
to "/boot/loader.conf" may help:

    kern.ipc.maxsockets="8192"
    kern.ipc.nmbclusters="32768"

John
-- 
  John Polstra
  John D. Polstra & Co., Inc.                        Seattle, Washington USA
  "Disappointment is a good sign of basic intelligence."  -- Chögyam Trungpa


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message