From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hannes Frederic Sowa <hannes@redhat.com>
Subject: Re: atomic operations bottleneck in the IPv6 stack
Date: Wed, 10 Dec 2014 18:16:03 +0100
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	"R89243@freescale.com" <R89243@freescale.com>,
	Madalin-Cristian Bucur <madalin.bucur@freescale.com>,
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To: "cristian.bercaru@freescale.com" <cristian.bercaru@freescale.com>
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On Mi, 2014-12-10 at 16:56 +0000, cristian.bercaru@freescale.com wrote:
> 
> It seems to me that the atomic operations on the IPv6 forwarding path
> are a bottleneck and they are not scalable with the number of cores.
> Am I right? What improvements can be brought to the IPv6 kernel code
> to make it less dependent of atomic operations/variables?

For a starter, something like the following commit:

commit d26b3a7c4b3b26319f18bb645de93eba8f4bdcd5
Author: Eric Dumazet <edumazet@google.com>
Date:   Tue Jul 31 05:45:30 2012 +0000

    ipv4: percpu nh_rth_output cache

Bye,
Hannes