i.MX ProcessorsのトピックRe: Poor ping performance - i.MX 8M Plus

Poor ping performance - i.MX 8M Plus

NG_R3 — Thu, 01 Dec 2022 13:03:39 GMT

Hi there,

I'm running imx-kernel 5.15.32 on a i.MX 8M Plus based custom board.
I have 2 nics:

# ethtool -i eth0 driver: fec version: 5.15.60-tq+g03954e24f9ca-rt49-t firmware-version: expansion-rom-version: bus-info: eth0 supports-statistics: yes supports-test: yes supports-eeprom-access: no supports-register-dump: yes supports-priv-flags: no # ethtool -i eth1 driver: st_gmac version: Jan_2016 firmware-version: expansion-rom-version: bus-info: supports-statistics: yes supports-test: no supports-eeprom-access: no supports-register-dump: yes supports-priv-flags: no

I'm experiencing poor results (average, and mdev) when sending ping to eth0, and better results when pinging eth1:

ping eth0 results: ... ... 64 bytes from 90.0.0.2: icmp_seq=34463 ttl=63 time=1.02 ms 64 bytes from 90.0.0.2: icmp_seq=34464 ttl=63 time=0.949 ms --- 90.0.0.2 ping statistics --- 100000 packets transmitted, 99999 received, 0.001% packet loss, time 107149ms rtt min/avg/max/mdev = 0.131/0.852/12.708/0.388 ms, pipe 2 ping eth1 results ... ... 64 bytes from 90.0.0.2: icmp_seq=34463 ttl=63 time=0.447 ms 64 bytes from 90.0.0.2: icmp_seq=34464 ttl=63 time=0.401 ms --- 90.0.0.2 ping statistics --- 100000 packets transmitted, 100000 received, 0% packet loss, time 100018ms rtt min/avg/max/mdev = 0.205/0.411/8.626/0.045 ms

Why is eth0 ping time double than eth1?

What can I do in order to achieve better performance with eth0?

Thanks a lot,

Nir.

Re: Poor ping performance - i.MX 8M Plus

NG_R3 — Tue, 13 Dec 2022 11:14:53 GMT

Hi,

I did some ping tests on the NXP i.mx8m-plus EVK with realtime edge 2.2.0. Numbers are average over 500 pings

ETH0 - 1.162ms
ETH1 - 0.312ms

Any comment on this issue would be great.

Thanks,

Nir.

Re: Poor ping performance - i.MX 8M Plus

Zhiming_Liu — Wed, 14 Dec 2022 01:26:03 GMT

Hello @NG_R3

The ENTE_QoS is assigned to eth1 instance. Only eth1 support TSN feature, you can refer this knowledge base:

https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/AVB-TSN-demo-on-i-MX8MP/ta-p/1123791

The ENET_QoS IP about eth1 support hardware multi-queue and traffic control .

Re: Poor ping performance - i.MX 8M Plus

NG_R3 — Wed, 14 Dec 2022 07:59:16 GMT

Hi Qmiller,

Thanks for your reply. I understand that ENET_QoS is attached to eth1, but my question regards eth0.

I did some ping tests on the NXP i.mx8m-plus EVK with realtime edge 2.2.0.

ETH0 - 1.162ms
ETH1 - 0.312ms

These numbers are similar on any i.MX8M Plus device that I could test. Custom boards and NXP's own EVK, running NXP's realtime edge.

Why is eth0 ping time double than eth1?

What can I do in order to achieve better performance with eth0?

Thanks a lot,

Nir.