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Date: Wed, 18 Jul 2012 18:41:00 +0400
From: "Alexander V. Chernikov" <melifaro@FreeBSD.org>
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To: Eugene Grosbein <egrosbein@rdtc.ru>
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Cc: Konstantin Belousov <kostikbel@gmail.com>, Doug Barton <dougb@freebsd.org>,
	Luigi Rizzo <rizzo@iet.unipi.it>, net@freebsd.org
Subject: Re: FreeBSD 10G forwarding performance @Intel
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On 17.07.2012 17:21, Eugene Grosbein wrote:
> 17.07.2012 06:23, Konstantin Belousov пишет:
>
>> I do not think that your 'per-cpu' counter are correct. The thread
>> migration or rescheduling causes the fetch or update of the wrong
>> per-cpu structure. This allows parallel updates with undefined
>> consequences.
>
>> From practical point of view, I'like to state that most of us do NOT
> need scientifically exact ipfw counters values when pushing hardware to its maximum.
>
> Personaly, I'd like to have tunable that gives me another 15% of speed
> at cost of bad ipfw counters I don't use anyway.
It seems that this can be done even with sysctl.
The same approach can be applied to per-cpu interface counters (and 
global per-protocol statistics).

>
> Eugene Grosbein
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-- 
WBR, Alexander