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Date: Mon, 05 Oct 2009 10:03:16 -0700
From: Julian Elischer <julian@elischer.org>
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To: Luigi Rizzo <rizzo@iet.unipi.it>
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Cc: rihad <rihad@mail.ru>, Eugene Grosbein <eugen@kuzbass.ru>,
	freebsd-net@freebsd.org
Subject: Re: dummynet dropping too many packets
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Luigi Rizzo wrote:

>> 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)

it all depends on the characteristics of the traffic

you need different queue lengths if it is just a small number of high 
speeed sessions (and mayne a large number of slow speed sessions),
or if it is a larger number of medium speed sessions.

Is it possible to know what sessions are losing packets?