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Date: Tue, 6 Jul 2004 13:33:43 -0700
From: "David S. Miller" <davem@redhat.com>
To: Stephen Hemminger <shemminger@osdl.org>
Cc: jbglaw@lug-owl.de, linux-net@vger.kernel.org, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH] fix tcp_default_win_scale.
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On Tue, 6 Jul 2004 13:31:46 -0700
Stephen Hemminger <shemminger@osdl.org> wrote:

> The default tcp_rmem[2] is 174760, so we only need a wscale of 2 to represent
> that. We were sending 7.

It's only going to paper over this problem, because a window scale
of 2 still gets edited by the firewalls yet doesn't cause the
kind of damage 7 does.

Also, using a value of 7 is very safe, because it handles even the
tinyest of MTU's in use today (512 byte SLIP connections, for example
can still advertise sub-MTU sized chunks in the window).  Since
a window scale of 7 allows a granularity of 128 octets.