From owner-freebsd-hackers  Wed Oct  8 14:34:57 1997
Return-Path: <owner-freebsd-hackers>
Received: (from root@localhost)
          by hub.freebsd.org (8.8.7/8.8.7) id OAA16001
          for hackers-outgoing; Wed, 8 Oct 1997 14:34:57 -0700 (PDT)
          (envelope-from owner-freebsd-hackers)
Received: from mail.cdsnet.net (mail.cdsnet.net [204.118.244.5])
          by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id OAA15994
          for <hackers@FreeBSD.ORG>; Wed, 8 Oct 1997 14:34:52 -0700 (PDT)
          (envelope-from mrcpu@cdsnet.net)
Received: from mail.cdsnet.net (mail.cdsnet.net [204.118.244.5])
	by mail.cdsnet.net (8.8.6/8.8.6) with SMTP id OAA09279;
	Wed, 8 Oct 1997 14:34:24 -0700 (PDT)
Date: Wed, 8 Oct 1997 14:34:23 -0700 (PDT)
From: Jaye Mathisen  <mrcpu@cdsnet.net>
To: Joerg Wunsch <joerg_wunsch@uriah.heep.sax.de>
cc: hackers@FreeBSD.ORG
Subject: Re: A TCP problem, plus solution!  (3.0-current)
In-Reply-To: <19971008215018.SO62644@uriah.heep.sax.de>
Message-ID: <Pine.NEB.3.95.971008143405.25558g-100000@mail.cdsnet.net>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Sender: owner-freebsd-hackers@FreeBSD.ORG
X-Loop: FreeBSD.org
Precedence: bulk


Must've just missed it, as I cvsup'd yesterday sometime.

On Wed, 8 Oct 1997, J Wunsch wrote:

> As Jaye Mathisen wrote:
> 
> > I traced it to a sysctl I had in /etc/rc.local that bumped the tcp
> > recvspace to 65536.
> > 
> > Resetting it to the default clears the problem up.
> 
> You are not running -current. ;-)
> 
> RCS file: /home/cvs/src/sys/netinet/tcp_output.c,v
> ...
> revision 1.27
> date: 1997/10/07 21:10:06;  author: fenner;  state: Exp;  lines: +3 -3
> Don't allow the window to be increased beyond what is possible to
> represent in the TCP header.  The old code did effectively:
>         win = min(win, MAX_ALLOWED);
>         win = max(win, what_i_think_i_advertised_last_time);
> so if what_i_think_i_advertised_last_time is bigger than can be
> represented in the header (e.g. large buffers and no window scaling)
> then we stuff a too-big number into a short.  This fix reverses the
> order of the comparisons.
> 
> PR:             kern/4712
> 
> -- 
> cheers, J"org
> 
> joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE
> Never trust an operating system you don't have sources for. ;-)
>