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Date: Fri, 2 Sep 2005 17:48:07 +0400
From: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
To: John Heffner <jheffner@psc.edu>
Cc: Ion Badulescu <lists@limebrokerage.com>,
       "David S. Miller" <davem@davemloft.net>, linux-net@vger.kernel.org,
       linux-kernel@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: Possible BUG in IPv4 TCP window handling, all recent 2.4.x/2.6.x kernels
Message-ID: <20050902134807.GB12617@yakov.inr.ac.ru>
References: <Pine.LNX.4.61.0509011713240.6083@guppy.limebrokerage.com> <20050901.154300.118239765.davem@davemloft.net> <Pine.LNX.4.61.0509011845040.6083@guppy.limebrokerage.com> <2d02c76a84655d212634a91002b3eccd@psc.edu>
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Hello!

> If you overflow the socket's memory bound, it ends up calling 
> tcp_clamp_window().  (I'm not sure this is really the right thing to do 
> here before trying to collapse the queue.)

Collapsing is too expensive procedure, it is rather an emergency measure.
So, tcp collapses queue, when it is necessary, but it must reduce window
as well.

Alexey