On Tue, 3 Nov 2015 17:18:31 -0500 Kyle Larose <eomereadig at gmail.com> wrote:
> On Tue, Nov 3, 2015 at 5:05 PM, Stephen Hemminger > <stephen at 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.
