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Date:   Fri, 5 Apr 2019 12:51:51 +0200
From:   Florian Westphal <fw@strlen.de>
To:     Toke =?iso-8859-15?Q?H=F8iland-J=F8rgensen?= <toke@redhat.com>
Cc:     Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>,
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Subject: Re: NAT performance regression caused by vlan GRO support
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Toke Høiland-Jørgensen <toke@redhat.com> wrote:
> As a first approximation, maybe just:
> 
> if (!has_hardware_cksum_offload(netdev) && link_rate(netdev) <= 1Gbps)
>   disable_gro();

I don't think its a good idea.  For local delivery case, there is no
way to avoid the checksum cost, so might as well have GRO enabled.