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From: David Miller <davem@davemloft.net>
Subject: Re: TCP rx window autotuning harmful at LAN context
Date: Wed, 11 Mar 2009 06:25:23 -0700 (PDT)
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From: Eric Dumazet <dada1@cosmosbay.com>
Date: Wed, 11 Mar 2009 10:11:10 +0100

> I am interested to know how use AQM in practice.

You just need RED, no need for ECN or anything like that.

RED will drop randomly when a certain percentage of the backlog queue
is consumed, and then behave like tail-drop after the next
configured threshold is reached.

It prevents TCPs from synchronizing, which is what happens with
pure tail-drop routers.