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From:   Eric Dumazet <edumazet@google.com>
Date:   Tue, 12 Jan 2021 13:32:56 +0100
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Subject: Re: [PATCH net-next 0/5] skbuff: introduce skbuff_heads bulking and reusing
To:     Alexander Lobakin <alobakin@pm.me>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Edward Cree <ecree@solarflare.com>,
        Jonathan Lemon <jonathan.lemon@gmail.com>,
        Willem de Bruijn <willemb@google.com>,
        Miaohe Lin <linmiaohe@huawei.com>,
        Steffen Klassert <steffen.klassert@secunet.com>,
        Guillaume Nault <gnault@redhat.com>,
        Yadu Kishore <kyk.segfault@gmail.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        netdev <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Tue, Jan 12, 2021 at 11:56 AM Alexander Lobakin <alobakin@pm.me> wrote:
>

>
> Ah, I should've mentioned that I use UDP GRO Fraglists, so these
> numbers are for GRO.
>

Right, this suggests UDP GRO fraglist is a pathological case of GRO,
not saving memory.

Real GRO (TCP in most cases) will consume one skb, and have page
fragments for each segment.

Having skbs linked together is not cache friendly.

So I would try first to make this case better, instead of trying to
work around the real issue.