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From: Eric Dumazet <eric.dumazet@gmail.com>
To: dave taht <dave.taht@gmail.com>
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Date: Sun, 06 May 2012 07:18:01 +0200
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Cc: codel@lists.bufferbloat.net,
	Dave =?ISO-8859-1?Q?T=E4ht?= <dave.taht@bufferbloat.net>
Subject: Re: [Codel] [PATCH v5] pkt_sched: codel: Controlled Delay AQM
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On Sat, 2012-05-05 at 16:19 -0700, dave taht wrote:

> I don't buy it. See previous mail.
> 
> count - some_x sure.

It depends if some_x is a constant or not.

TCP cwnd is divided by two after a drop.

cwnd = cwnd >> 1;

If we did cwnd = cwnd - some_x; It would no work very well.


I am now experimenting :

q->count = max(1U, q->count - (q->count >> 2));

(count = 75% of count)