Am 5. August 2016 23:01:10 MESZ, schrieb Arend Van Spriel <arend.vanspriel@xxxxxxxxxxxx>: >Op 5 aug. 2016 22:46 schreef "Jörg Krause" ><joerg.krause@embedded.rocks>: >> >> Hi, >> >> I'm using a custom ARM board with an BCM43362 wifi chip from >Broadcom. >> The wifi chip is attached via SDIO to the controller with a clock of >> 48MHz. Linux kernel version is 4.7. >> >> When measuring the network bandwidth with iperf3 I get a bandwith of >> only around 5 Mbps. I found a similar thread at the Broadcom >community >> [1] where the test was done with a M4 CPU + BCM43362 and an average >> result of 3.3 Mbps. >> >> Interestingly, a BCM43362 Wi-Fi Dev Kit [2] notes a TCP data >throughput >> greater than 20 Mbps. >> >> Why is the throughput I measured much lower? Note that I measured >> several times with almost no neighbor devices or networks. >> >> This is a test sample measured with iperf3: >> >> $ iperf3 -c 192.168.2.1 -i 1 -t 10 >> Connecting to host 192.168.2.1, port 5201 >> [ 4] local 192.168.2.155 port 36442 connected to 192.168.2.1 >port >> 5201 >> [ ID] Interval Transfer Bandwidth Retr Cwnd >> [ 4] 0.00-1.00 sec 615 KBytes 5.04 Mbits/sec 0 56.6 >> KBytes >> [ 4] 1.00-2.00 sec 622 KBytes 5.10 Mbits/sec 0 84.8 >> KBytes >> [ 4] 2.00-3.00 sec 625 KBytes 5.12 Mbits/sec 0 113 >> KBytes >> [ 4] 3.00-4.00 sec 571 KBytes 4.68 Mbits/sec 0 140 >> KBytes >> [ 4] 4.00-5.00 sec 594 KBytes 4.87 Mbits/sec 0 167 >> KBytes >> [ 4] 5.00-6.00 sec 628 KBytes 5.14 Mbits/sec 0 195 >> KBytes >> [ 4] 6.00-7.00 sec 619 KBytes 5.07 Mbits/sec 0 202 >> KBytes >> [ 4] 7.00-8.00 sec 608 KBytes 4.98 Mbits/sec 0 202 >> KBytes >> [ 4] 8.00-9.00 sec 602 KBytes 4.93 Mbits/sec 0 202 >> KBytes >> [ 4] 9.00-10.00 sec 537 KBytes 4.40 Mbits/sec 0 202 >> KBytes >> - - - - - - - - - - - - - - - - - - - - - - - - - >> [ ID] Interval Transfer Bandwidth Retr >> [ 4] 0.00-10.00 sec 5.88 MBytes 4.93 >> Mbits/sec 0 sender >> [ 4] 0.00-10.00 sec 5.68 MBytes 4.76 >> Mbits/sec receiver > >Not overly familiar with iperf3. Do these lines mean you are doing >bidirectional test, ie. upstream and downstream at the same time. >Another >thing affecting tput could be power-save. No, iperf3 does not support bidrectional test. Power-save is turned off. -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
