Flow ID, LACP, and igb

[Adrian Chadd]

> Not sure about igb, but ixgbe (according to advanced RX descriptor
> format, 7.1.6.2 @ 82599 datasheet) can provide 'real' RSS value which
> can be used in m_flowid instead of NIC queue id.
>
> (And, by the way, another RSS-related problem:
> there are cases when setting flowid does more harm, for example -
> PPPoE frames always being received at Q0.
> Partially this can be solved by analyzing RSS type from the same RX
> descriptor format (e.g. don't set flowid for RSS type 0x0), but there
> are other cases like GRE tunneling (where you probably want to perform
> deeper inspection in SW).
>
> So, can we have some kind of per-NIC sysctl disabling setting flowid
> on given port?
>
> (Yes, this should be in some kind of `ethtool` binary but we still
> don't have it..)
> )
>

What specifically are you asking for? Disabling the flowid tagging of
mbufs? Or changing the LACP hashing?

You can configure LACP to not use the flowid from the NIC and do the
hashing yourself.


-adrian