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

Eric Dumazet
2013-11-08T02:42:41Z

On Fri, 2013-11-08 at 10:17 +0800, Herbert Xu wrote:

> Oh no let's keep it as it is indeed a great cleanup and improvement
> for LRO. We can however remove the bits that relate to GRO.

What about doing a benchmark first ?

I benchmarked the 'locally delivered' traffic, not the forwarding one.

That's why I am not comfortable of having large GRO packets that need
to be segmented.

You tell us hardware advantage of TSO is negligible, this is not
what I observe today on many platforms.

A normal TSO packets with 16 MSS setups a ~17 DMA descriptors,
while GSO requires 2 DMA descriptors per MSS, plus a lot of overhead
in sk_buff allocation/deallocation.