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Subject: Re: (removing mbuf flowid setup in flowtable.c)
From: Adrian Chadd <adrian@freebsd.org>
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On 30 January 2014 07:18, Adrian Chadd <adrian@freebsd.org> wrote:
> Hi,
>
> I'd like to disable the code in flowtable.c that assigns the mbuf flowid.
>
> I'd like to ensure that any mbuf flowid that's set is (eventually)
> going to be consistently toeplitz in the future (to match what NICs
> are doing on the RX side) and this may cause the flowid to be set to
> something completely different.
>
> I've only done some light production testing with this so far, to no
> visible ill effects.
>
> What do people think?

Someone pointed out privately that doing this would mean that UDP
flows without flow ids would suddenly not have flowids any longer and
thus wouldn't use multiple output queues.

So, I'll leave this alone for now until I can import the toeplitz hash
code into -HEAD and add an option to tag outbound udp frames with this
particular flowid hash.

Thanks,


-a


> Thanks,
>
>
> -a
>
>
> Index: sys/net/flowtable.c
> ===================================================================
> --- sys/net/flowtable.c (revision 261001)
> +++ sys/net/flowtable.c (working copy)
> @@ -1102,10 +1102,12 @@
>   if (af == AF_INET6)
>   fle = flowtable_lookup_mbuf6(ft, m);
>  #endif
> +#if 0
>   if (fle != NULL && m != NULL && (m->m_flags & M_FLOWID) == 0) {
>   m->m_flags |= M_FLOWID;
>   m->m_pkthdr.flowid = fle->f_fhash;
>   }
> +#endif
>   return (fle);
>  }