Hello,
I test my M2+ boards (several) with iperf (ver. 2.0.1) and iperf3 (ver. 3.6 with cJSON 1.5.2) and I noticed strange packet losses reported by iperfs (regardless of version). Perhaps someone has experienced similar problems? I’m not sure if these are the iperf problem or the BananaPi boards are faulty.
The results below are collected with the iperf3 server running with default settings (iperf3 -s -i 1). (results from iperf confirm these findings, so I will skip them). For really low loads below 30mbps iperf3 reports no drops, later we have an increasing number of drops - note 50% (!!!) for 500mbps and then we are back at 3% drop for 1000mbps.
if I test my interface with netstat (netstat -i), no drops are reported on the interface:
Kernel Interface table
Iface MTU RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg
eth0 1500 609836 0 0 0 804 0 0 0 BMRU
lo 65536 3 0 0 0 3 0 0 0 LRU
wlan0 1500 0 0 0 0 0 0 0 0 BMU
my kernel version
Linux bpi2 5.1.1-BPI-Kernel #1 SMP Thu Aug 22 13:53:49 CST 2019 armv7l GNU/Linux
pi@bpi2:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Debian
Description: Debian GNU/Linux 10 (buster)
Release: 10
Codename: buster
Thanks in advance for any help!
============================ iperf3 results
iperf3 -c 192.168.1.11 -u -b 1000m -t 3
[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
[ 5] 0.00-3.00 sec 339 MBytes 949 Mbits/sec 0.000 ms 0/245798 (0%) sender
[ 5] 0.00-3.00 sec 329 MBytes 920 Mbits/sec 0.011 ms 7301/245683 (3%) receiver
iperf3 -c 192.168.1.11 -u -b 500m -t 3
[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
[ 5] 0.00-3.00 sec 179 MBytes 500 Mbits/sec 0.000 ms 0/129456 (0%) sender
[ 5] 0.00-3.00 sec 100 MBytes 281 Mbits/sec 0.015 ms 56743/129456 (44%) receiver
for iperf3 -c 192.168.1.11 -u -b 100m -t 3
[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
[ 5] 0.00-3.00 sec 35.8 MBytes 100 Mbits/sec 0.000 ms 0/25892 (0%) sender
[ 5] 0.00-3.00 sec 33.0 MBytes 92.3 Mbits/sec 0.033 ms 1975/25892 (7.6%) receiver
for iperf3 -c 192.168.1.11 -u -b 50m -t 3
[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
[ 5] 0.00-3.00 sec 17.9 MBytes 50.0 Mbits/sec 0.000 ms 0/12946 (0%) sender
[ 5] 0.00-3.02 sec 17.7 MBytes 49.1 Mbits/sec 0.400 ms 98/12911 (0.76%) receiver