Re: [PATCH v4 net-next] net: introduce dev_set_forwarding()

Eric Dumazet
2013-11-08T05:40:14Z

On Fri, 2013-11-08 at 13:21 +0800, Herbert Xu wrote:

>
> My point is that even if you did that GRO with your frag_list
> patch should still be a win because the stack prior to the qdisc
> gets run once instead of two or three times.
>

OK, lets me repeat again.

64KB packet receive/aggregation time is more than 540 us on 1Gbps link.

The fact that you split or not the packet at transmit is quite
irrelevant, its already too late.

The problem is not the egress, its GRO if it can aggregate too big
packets.

Most of GRO/GSO benefits are already there with 16 MSS skbs,
we do not gain that much using 44/45 MSS skbs, but increase the
Store-and-Forward Delay by 200 %