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Date: Thu, 16 Jan 2014 11:06:47 -0800
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Subject: Re: ECMP hash keys?
From: Adrian Chadd <adrian@freebsd.org>
To: Nikolay Denev <nike_d@cytexbg.com>
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Cc: "Alexander V. Chernikov" <melifaro@freebsd.org>,
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On 16 January 2014 08:02, Nikolay Denev <nike_d@cytexbg.com> wrote:

> Hi Adrian,
>
> Probably a stupid question, but I'm trying to understand more about this,
> so basically the benefit of using essentially an additive hash function would be
> that both directions of the same flow/connection would end up for
> processing on the same core?

Yes. For TCP workloads where you have a lot of shared state being
changed in the transmit and receive direction, there's a _lot_ of lock
contention going on all over the place.



-a