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Date: Fri, 23 Jan 2009 12:44:20 +0300
From: Oleg Bulyzhin <oleg@FreeBSD.org>
To: Luigi Rizzo <rizzo@iet.unipi.it>
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Cc: stable@FreeBSD.org, re@FreeBSD.org
Subject: Re: backporting dummynet's q_time change ? (svn 184414)
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On Fri, Jan 23, 2009 at 10:23:12AM +0100, Luigi Rizzo wrote:

> this is also in RELENG_7 but i am not sure whether this workaround
> has any drawback e.g., when curr_time passes a 32-bit boundary
> there seems to be an incorrect setting of q->numbytes

Workaround is fine in average. It may fail for:
1) _very_ idle flow (more than 2^32 ticks) while calculating q->avg
2) any flow once per 2^32 ticks
then q_time will be updated and things will be ok again.

-- 
Oleg.

================================================================
=== Oleg Bulyzhin -- OBUL-RIPN -- OBUL-RIPE -- oleg@rinet.ru ===
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