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

[Stephen Hemminger <stephen@networkplumber.org>]

On Tue, 3 Nov 2015 17:18:31 -0500
Kyle Larose <eomereadig@gmail.com> wrote:

> 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.

No. configuration is the enemy of usability.
Why does DPDK have to behave differently than BSD and Linux, what possible
value could this be to the end user?

> 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.