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Date:   Fri, 22 Apr 2022 10:10:45 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Eric Dumazet <edumazet@google.com>
Cc:     Eric Dumazet <eric.dumazet@gmail.com>,
        "David S . Miller" <davem@davemloft.net>,
        Paolo Abeni <pabeni@redhat.com>,
        netdev <netdev@vger.kernel.org>
Subject: Re: [PATCH net-next] net: generalize skb freeing deferral to
 per-cpu lists
Message-ID: <20220422101045.352eb086@kernel.org>
In-Reply-To: <CANn89iLK5i9y5=iAHS=8+SinGkmGgEXR=xk=ATpnXPakD1j-vQ@mail.gmail.com>
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On Fri, 22 Apr 2022 09:50:33 -0700 Eric Dumazet wrote:
> The thing is that with a typical number of RX queues (typically 16 or
> 32 queues on a 100Gbit NIC),
> there is enough sharding for this spinlock to be a non-issue.
> 
> Also, we could quite easily add some batching in a future patch, for
> the cases where the number of RX queues
> is too small.
> 
> (Each cpu could hold up to 8 or 16 skbs in a per-cpu cache, before
> giving them back to alloc_cpu(s))

I was wondering if we want to keep the per-socket queue for the
batching but you're right, per CPU batch is better anyway if needed.