On Tue, 3 Nov 2015 14:30:41 +0000 "Van Haaren, Harry" <harry.van.haaren at intel.com> wrote:
> Hi Keith, > > > From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Wiles, Keith > <snip> > > Hmm, I just noticed I did not include the FCS bytes. Does the NIC include > > FCS bytes in the > > counters? Need to verify that one and if not then it becomes a bit more > > complex. > > The Intel NICs count packet sizes inclusive of CRC / FCS, from eg the > ixgbe/82599 datasheet: > "This register includes bytes received in a packet from the <Destination > Address> field through the <CRC> field, inclusively." > > -Harry 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.
