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From: Eugene Grosbein <egrosbein@rdtc.ru>
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To: Konstantin Belousov <kostikbel@gmail.com>
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Cc: Luigi Rizzo <rizzo@iet.unipi.it>, Doug Barton <dougb@freebsd.org>,
	"Alexander V. Chernikov" <melifaro@freebsd.org>, net@freebsd.org
Subject: Re: FreeBSD 10G forwarding performance @Intel
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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.

Eugene Grosbein