From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Van Haaren, Harry" <harry.van.haaren@intel.com>
Subject: Re: Virtio xstats problem
Date: Fri, 26 Feb 2016 14:29:19 +0000
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To: Igor Ryzhov <iryzhov@nfware.com>, "dev@dpdk.org" <dev@dpdk.org>
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> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Igor Ryzhov
> I found some problem with virtio xstats counters.
>=20
> Example:
>=20
> rx_good_packets: 3
> rx_good_bytes: 180
> rx_errors: 0
>=20
> rx_q0_good_packets: 3
> rx_q0_good_bytes: 180
> rx_q0_errors: 0
>=20
> rx_q0_multicast_packets: 3
> rx_q0_broadcast_packets: 1
> rx_q0_undersize_packets: 3

> It means that undersize packets are counted as good packets instead of er=
rors.

Are you sending 64 byte packets? There are no 4 bytes of CRC on virtual
interfaces, so 60 bytes per packet is OK.

> Or maybe
> size of packet is calculated wrong.
> I don't have time now to check it more deeply - I can do it sometime late=
r, but maybe
> someone want to help.

Are the packets multicast or broadcast?
It looks like one of the counters there is wrong.

> PS. Is it a common practice to count broadcast packets twice - in broadca=
st and multicast
> counters?

No packet should be counted twice - it must be put into one bucket of mutli=
, broad or unicast.

-Harry