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

Herbert Xu
2013-11-08T03:24:07Z

On Thu, Nov 07, 2013 at 06:51:53PM -0800, Eric Dumazet wrote:
> On Thu, 2013-11-07 at 18:42 -0800, Eric Dumazet wrote:
>
> > 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.
>
> Not mentioning fact that a 64KB packet is adding latencies, since high
> prio packets have to wait the whole preceding 64KB packet has left the
> host.

That would be a bug in the GRO code since a high prio packet
shouldn't have been merged in the first place and therefore
the usual priority mechanism should allow it to preempt the
64KB packet.

Cheers,
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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