Slow Iperf3 speed between Centos server and Andriod/rpi devices.

[harvestmoon88]

Hello

I am having a very slow transfer speed between my android box, rpi (different OS were tested) and my centos home server when I do perf3 test.

the issue is only when android tv, andriod tablet or RPI3 in server mode during iperf3 test.

Windows 10 and centos speeds both ways are fine.

the things I have tried:

• using LAN and Wifi connection.

• Tried using speedtest-cli on RPI results

Testing download speed…
Download: 92.89 Mbit/s
Testing upload speed…
Upload: 47.98 Mbit/s

• Tested different cable and different router.

• tested with android tv box, android tablet, rpi3 box (even different flavors such as osmc, libreelec, plain debian, ubuntu server, raspian).

Iperf Centos(client) to RPI(server)
Connecting to host 192.168.0.129, port 5201
[ 4] local 192.168.0.167 port 35484 connected to 192.168.0.129 port 5201
[ ID] Interval Transfer Bandwidth Retr Cwnd
[ 4] 0.00-1.00 sec 287 KBytes 2.35 Mbits/sec 39 2.83 KBytes
[ 4] 1.00-2.00 sec 157 KBytes 1.29 Mbits/sec 19 5.66 KBytes
[ 4] 2.00-3.00 sec 158 KBytes 1.30 Mbits/sec 17 2.83 KBytes
[ 4] 3.00-4.00 sec 238 KBytes 1.95 Mbits/sec 19 5.66 KBytes
[ 4] 4.00-5.00 sec 153 KBytes 1.25 Mbits/sec 17 2.83 KBytes
[ 4] 5.00-6.00 sec 158 KBytes 1.30 Mbits/sec 20 2.83 KBytes
[ 4] 6.00-7.00 sec 158 KBytes 1.30 Mbits/sec 16 2.83 KBytes
[ 4] 7.00-8.00 sec 157 KBytes 1.29 Mbits/sec 20 2.83 KBytes
[ 4] 8.00-9.00 sec 156 KBytes 1.27 Mbits/sec 16 2.83 KBytes
[ 4] 9.00-10.00 sec 156 KBytes 1.27 Mbits/sec 20 2.83 KBytes

[ ID] Interval Transfer Bandwidth Retr
[ 4] 0.00-10.00 sec 1.74 MBytes 1.46 Mbits/sec 203 sender
[ 4] 0.00-10.00 sec 1.68 MBytes 1.41 Mbits/sec receiver

Iperf Centos(server) RPI (client)
Accepted connection from 192.168.0.129, port 57916
[ 5] local 192.168.0.167 port 5201 connected to 192.168.0.129 port 57918
[ ID] Interval Transfer Bandwidth
[ 5] 0.00-1.00 sec 10.8 MBytes 90.7 Mbits/sec
[ 5] 1.00-2.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 2.00-3.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 3.00-4.00 sec 11.2 MBytes 94.2 Mbits/sec
[ 5] 4.00-5.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 5.00-6.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 6.00-7.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 7.00-8.00 sec 11.2 MBytes 94.2 Mbits/sec
[ 5] 8.00-9.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 9.00-10.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 10.00-10.04 sec 474 KBytes 93.9 Mbits/sec

[ ID] Interval Transfer Bandwidth
[ 5] 0.00-10.04 sec 0.00 Bytes 0.00 bits/sec sender
[ 5] 0.00-10.04 sec 112 MBytes 93.8 Mbits/sec receiver

[BitEater]

try it with smaller pakets, iperf3 ... -M 1280
to findMTU issues.