Hi all,
I'm experiencing a poor WLAN performance with the DM3730 Torpedo module if using it in ad-hoc mode. Especially, the uplink speed (sending from the Torpedo module) is very low. The module is used in the development kit and an antenna is connected to it. Both sides are running iperf version 2.0.5.
My measurement results are the following:
# iperf -i 5 -t 30 -c 192.168.254.101 -r -w 128K
------------------------------------------------------------
Server listening on TCP port 5001
TCP window size: 256 KByte (WARNING: requested 128 KByte)
------------------------------------------------------------
------------------------------------------------------------
Client connecting to 192.168.254.101, TCP port 5001
TCP window size: 256 KByte (WARNING: requested 128 KByte)
------------------------------------------------------------
[ 5] local 192.168.254.123 port 37057 connected with 192.168.254.101 port 5001
[ ID] Interval Transfer Bandwidth
[ 5] 0.0- 5.0 sec 5.00 MBytes 8.39 Mbits/sec
[ 5] 5.0-10.0 sec 5.00 MBytes 8.39 Mbits/sec
[ 5] 10.0-15.0 sec 4.88 MBytes 8.18 Mbits/sec
[ 5] 15.0-20.0 sec 5.00 MBytes 8.39 Mbits/sec
[ 5] 20.0-25.0 sec 4.88 MBytes 8.18 Mbits/sec
[ 5] 25.0-30.0 sec 4.88 MBytes 8.18 Mbits/sec
[ 5] 0.0-30.1 sec 29.8 MBytes 8.28 Mbits/sec
[ 4] local 192.168.254.123 port 5001 connected with 192.168.254.101 port 41971
[ 4] 0.0- 5.0 sec 390 KBytes 639 Kbits/sec
[ 4] 5.0-10.0 sec 389 KBytes 637 Kbits/sec
[ 4] 10.0-15.0 sec 383 KBytes 628 Kbits/sec
[ 4] 15.0-20.0 sec 397 KBytes 650 Kbits/sec
[ 4] 20.0-25.0 sec 380 KBytes 622 Kbits/sec
[ 4] 25.0-30.0 sec 396 KBytes 649 Kbits/sec
[ 4] 0.0-32.8 sec 2.50 MBytes 638 Kbits/sec
I've also tested the Torpedo module as a WLAN station connected to an access point. Then the measurement results look better. The uplink speed is even higher now than the downlink.
$ iperf -i 5 -t 30 -c 192.168.254.101 -r -w 128K
------------------------------------------------------------
Server listening on TCP port 5001
TCP window size: 256 KByte (WARNING: requested 128 KByte)
------------------------------------------------------------
------------------------------------------------------------
Client connecting to 192.168.254.101, TCP port 5001
TCP window size: 256 KByte (WARNING: requested 128 KByte)
------------------------------------------------------------
[ 3] local 192.168.254.100 port 57472 connected with 192.168.254.101 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0- 5.0 sec 7.50 MBytes 12.6 Mbits/sec
[ 3] 5.0-10.0 sec 7.00 MBytes 11.7 Mbits/sec
[ 3] 10.0-15.0 sec 7.00 MBytes 11.7 Mbits/sec
[ 3] 15.0-20.0 sec 7.25 MBytes 12.2 Mbits/sec
[ 3] 20.0-25.0 sec 7.38 MBytes 12.4 Mbits/sec
[ 3] 25.0-30.0 sec 7.38 MBytes 12.4 Mbits/sec
[ 3] 0.0-30.1 sec 43.6 MBytes 12.2 Mbits/sec
[ 5] local 192.168.254.100 port 5001 connected with 192.168.254.101 port 60365
[ 5] 0.0- 5.0 sec 10.4 MBytes 17.5 Mbits/sec
[ 5] 5.0-10.0 sec 10.3 MBytes 17.2 Mbits/sec
[ 5] 10.0-15.0 sec 10.3 MBytes 17.3 Mbits/sec
[ 5] 15.0-20.0 sec 10.3 MBytes 17.4 Mbits/sec
[ 5] 20.0-25.0 sec 10.3 MBytes 17.2 Mbits/sec
[ 5] 25.0-30.0 sec 10.2 MBytes 17.1 Mbits/sec
[ 5] 0.0-30.0 sec 61.9 MBytes 17.3 Mbits/sec
What I also recognized is that the CPU usage of the torpedo is high when it is in station mode (both when sending and when receiving). This means that the CPU is around 10% idle and 60-70% irq/312-wl12xx. However, the CPU usage is low when the module is in ad-hoc mode and it is sending (around 87% idle, 8% irq/312-wl12xx).
Any ideas how to improve the WLAN performance in ad-hoc mode? Has anyone experienced the same issue?
Thanks