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Date: Fri, 20 Mar 2015 19:56:37 +0100
From: Hans Petter Selasky <hps@selasky.org>
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To: Adrian Chadd <adrian@freebsd.org>
Subject: Re: Fragment questions
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Cc: Emeric POUPON <emeric.poupon@stormshield.eu>,
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On 03/20/15 19:02, Adrian Chadd wrote:
> On 20 March 2015 at 10:58, Hans Petter Selasky <hps@selasky.org> wrote:
>> On 03/20/15 14:31, Emeric POUPON wrote:
>>>
>>> - in the ip_newid macro, we do "htons(V_ip_id++))" if we do not use
>>> randomized id.
>>
>>> In multi core systems, we may emit successive packets with the same id.
>>
>> Will using a mutex or an atomic macro fix this issue when incrementing the
>> V_ip_id ?
>
> It will, but it'll ping-pong between multiple cores and slow things
> down at high pps.
>

Hi,

Maybe we can have the V_ip_id per CPU and use the lower 8-bits as random 
CPU core number?

OK?

--HPS