Re: [dpdk-dev] ixgbe: account more Rx errors Issue

[Andriy Berestovskyy <aber@semihalf.com>]

Hi Maryam,
Please see below.

> XEC counts the Number of receive IPv4, TCP, UDP or SCTP XSUM errors

Please note than UDP checksum is optional for IPv4, but UDP packets with zero checksum hit XEC.

> And general crc errors counts Counts the number of receive packets with CRC errors.

Let me explain you with an example.

DPDK 2.0 behavior:
host A sends 10M IPv4 UDP packets (no checksum) to host B
host B stats: 9M ipackets + 1M ierrors (missed) = 10M

DPDK 2.1 behavior:
host A sends 10M IPv4 UDP packets (no checksum) to host B
host B stats: 9M ipackets + 11M in ierrors (1M missed + 10M XEC) = 20M?

> So our options are we can:
> 1. Add only one of these into the error stats.
> 2. We can introduce some cooking of stats in this scenario, so only add either or if they are equal or one is higher than the other.
> 3. Add them all which means you can have more errors than the number of received packets, but TBH this is going to be the case if your packets have multiple errors anyway.

4. ierrors should reflect NIC drops only.
XEC does not count drops, so IMO it should be removed from ierrors.

Please note that we still can access the XEC using rte_eth_xstats_get()


Regards,
Andriy