Is netmap jumbo frames broken in STABLE?

[Luigi Rizzo]

On Tue, Jun 7, 2016 at 2:43 PM, Andrey V. Elsukov <bu7cher at yandex.ru> wrote:

> On 07.06.16 15:22, Andrew Vylegzhanin wrote:
> > Just for support Luigi assumption.
> >
> > I've tested on 11.0-ALPHA1 (r301204).
> > Same situation with frame size 5166 and works _well_ with frame size
> 4032.
>
> This was changed in
>         https://svnweb.freebsd.org/base?view=revision&revision=283883
>
> In the ixgbe_init_locked() initialization of adapter->rx_mbuf_sz was
> limited to MJUMPAGESIZE. But I'm agree with Ryan, with this
> configuration it works more reliable.
>

​Nothing prevents modifying the configuration while the card
is in netmap mode, and reverting to the previous one
in regular mode. netmap allocates its own buffers and
if it fails the NIC just reverts back to regular mode.

This said, we can make netmap work with multiple buffers
also on NICs;
it is already supported in VALE. Just makes
the user code a bit less convenient.

cheers
luigi