From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] netem: markov loss model transition fix
Date: Fri, 25 Oct 2013 19:04:09 -0400 (EDT)
Message-ID: <20131025.190409.1394476393722866643.davem@davemloft.net>
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From: Hagen Paul Pfeifer <hagen@jauu.net>
Date: Tue, 22 Oct 2013 23:27:06 +0200

> The transition from markov state "3 => lost packets within a burst
> period" to "1 => successfully transmitted packets within a gap period"
> has no *additional* loss event. The loss already happen for transition
> from 1 -> 3, this additional loss will make things go wild.
> 
> E.g. transition probabilities:
> 
> p13:   10%
> p31:  100%
> 
> Expected:
> 
> Ploss = p13 / (p13 + p31)
> Ploss = ~9.09%
> 
> ... but it isn't. Even worse: we get a double loss - each time.
> So simple don't return true to indicate loss, rather break and return
> false.
> 
> Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>
> Cc: Stephen Hemminger <stephen@networkplumber.org>
> Cc: Eric Dumazet <edumazet@google.com>
> Cc: Stefano Salsano <stefano.salsano@uniroma2.it>
> Cc: Fabio Ludovici <fabio.ludovici@yahoo.it>
> Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>

Applied.