[ovs-discuss] Some issues about datapath and userspace.

[Jesse Gross]

On Thu, May 30, 2013 at 10:31 AM, zuo <zuoqy at 163.com> wrote:
> Thank you for providing the requested information.
> I found that "subfacet->slow_path_reason == 0" indicates packets is
> processed by fast path, so in this case the packet is directly forwarded by
> the kernel. If it is in slow-path such as "slow_controller", the packets
> will all be forwarded to userspace without buffering in kernel.  Do I
> understand correctly?

Yes, that's right.

> Another question. I learned that flow miss to the controller will be
> buffered in the userspace. If I send the entire packet to the controller
> (not just the 128 bytes of pakcet header), is it still buffered in
> userspace? Could I avoid for that?

Yes, it is still buffered and no you can't change it.