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Date: Mon, 5 Oct 2009 18:05:32 +0800
From: Eugene Grosbein <eugen@kuzbass.ru>
To: Luigi Rizzo <rizzo@iet.unipi.it>
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Cc: rihad <rihad@mail.ru>, freebsd-net@freebsd.org
Subject: Re: dummynet dropping too many packets
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On Mon, Oct 05, 2009 at 12:04:46PM +0200, Luigi Rizzo wrote:

> > The goal is to make sources of traffic to slow down, this is the only
> > way to descrease drops - any finite queue may be overhelmed with traffic.
> > Taildrop does not really help with this. GRED does much better.
> 
> i think the first problem here is figure out _why_ we have
> the drops, as the original poster said that queues are configured
> with a very large amount of buffer (and i think there is a
> misconfiguration somewhere because the mbuf stats do not make
> sense)

That may be very simple, f.e. wide uplink channel and policy that
dictates slower client speeds. Any taildrop queue would drop lots
of packets.

Eugene Grosbein