[dpdk-users] X710 DA2 (2x10G) performance 64B packets

[Tomáš Jánský]

Hello DPDK users,

I am having an issue concerning the performance of X710 DA2 (2x10G) NIC
when using testpmd (and also l2fwd) application on both ports.

HW and SW parameters:
CPUs: Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz x16
Disabled hyperthreading.
All used lcores and ports are on the same NUMA node (0).
Hugepages: 1024x 2MB on the NUMA node 0.
RAM: 64 GB

DPDK version: 18.05.1
Modue: IGB UIO
GCC version: 4.8.5

When using testpmd application only on one port:
./testpmd -b 0000:04:00.0 -n 4 --lcore=0 at 0,2 at 2 -- --socket-num=0
--nb-cores=1 --nb-ports=1 --numa --forward-mode=rxonly

14.63 Mpps (64B packet length) - 0.01% packets dropped

When using testmpd on both ports:
./testpmd -n 4 --lcore=0 at 0,2 at 2,4 at 4 -- --socket-num=0 --nb-cores=2
--nb-ports=2 --numa --forward-mode=rxonly

28.08 Mpps (64B packet length) - 3.47% packets dropped

Does anybody have an explanation why am I experiencing this performance
drop?
Any suggestion would be much appreciated.

Thank you
Tomas