Re: [dpdk-dev] How can I calculate/estimate pps(packet per seocond) and bps(bit per second) in DPDK pktg

[Kyle Larose <eomereadig@gmail.com>]

On Tue, Nov 3, 2015 at 5:05 PM, Stephen Hemminger
<stephen@networkplumber.org> wrote:

>
> IMHO this is a bug. Other drivers don't include the CRC, and the Intel driver
> only includes CRC in count for one direction, and depends on value of stripping flag.
>
> I sent a patch to fix this because our customers didn't like it when Rx != Tx bytes
> but there was somebody who liked including CRC.
>
> It really is a Cisco versus the world thing. Juniper/Linux/BSD all do NOT include
> CRC in counters and therefore that is what should be done.
>

Another option is to make whether or not the NIC counts the CRC in its
byte counters configurable, when supported, and also retrievable. I'm
concerned about the case where a NIC doesn't even have an option to
control whether or not it counts the CRC, and it *does* count it. In
that case, any software running on that NIC will behave
inconsistently. If it knew that it counted the CRC, it could adjust
for it.

If we put the option in now, then software written now could deal with
it gracefully. Combined with the ability to configure it, this may
satisfy use cases where knowing the full frame size is useful (for
example when looking at bit rates with small packets. 4 bytes is a big
difference for a 64-byte frame).

Of course, this may not be a problem worth solving. But, I figure it's
worth considering.