All of lore.kernel.org
 help / color / mirror / Atom feed
From: John Heffner <jheffner@psc.edu>
To: lists@andyfurniss.entadsl.com
Cc: netdev@vger.kernel.org
Subject: Re: Controlling TCP window size
Date: Tue, 16 May 2006 14:28:23 -0400	[thread overview]
Message-ID: <446A19C7.1000302@psc.edu> (raw)
In-Reply-To: <4469B251.3050901@andyfurniss.entadsl.com>

Andy Furniss wrote:
> 
> I've been doing some testing of my new wan connection and noticed that 
> when I specify a window with ip route it still changes after a while.

Looks like this is occurring in net/ipv4/tcp_input.c:tcp_rcv_space_adjust().

The problem really is that the window_clamp variable is overloaded. 
It's used as a kind of cache for rcvbuf -> window conversion, but also 
as a user-settable bound in window size.  On examination, it looks like 
this is also broken (in that window size won't increase) if a user does 
a setsockopt(SO_RCVBUF).  Can we make window_clamp a true clamp?  Then 
we can get rid of the hack of raising it in tcp_rcv_space_adjust().  I 
can cook up a patch if interested.

   -John

  reply	other threads:[~2006-05-16 18:28 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-05-16 11:06 Controlling TCP window size Andy Furniss
2006-05-16 18:28 ` John Heffner [this message]
2006-05-16 18:36   ` Andy Furniss
2006-05-16 18:48     ` John Heffner
2006-05-16 23:01   ` David S. Miller

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=446A19C7.1000302@psc.edu \
    --to=jheffner@psc.edu \
    --cc=lists@andyfurniss.entadsl.com \
    --cc=netdev@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.