Hello, Sorry if this is not the right place to ask this. But I didn't find an USB user mailing list. We have a custom TI DM3730 board using a Mentor Graphics's USB controller (musb_hdrc). We are using the usb ethernet gadget (g_ether) to create a point-to-point ethernet network between the board and a host PC. The problem is that even when the bus is USB 2.0 with a theoretical transfer rate of 480 Mbps, we are only getting about 55 Mbps from the host to the target and about 65 Mbps from the target to the host. We are pretty sure that the board can handle more traffic than that since with a fast Ethernet 100BASE-TX connection we get about 93 Mbps. Is correct to get so low traffic with the usb ethernet gadget? Here is the iperf log: $ iperf -c 10.0.0.2 -t 6 -i 1 -r -u -b 480M ------------------------------------------------------------ Client connecting to 10.0.0.2, UDP port 5001 Sending 1470 byte datagrams UDP buffer size: 112 KByte (default) ------------------------------------------------------------ [ 4] local 10.0.0.1 port 57539 connected with 10.0.0.2 port 5001 ------------------------------------------------------------ Server listening on UDP port 5001 Receiving 1470 byte datagrams UDP buffer size: 112 KByte (default) ------------------------------------------------------------ [ ID] Interval Transfer Bandwidth [ 4] 0.0- 1.0 sec 6.73 MBytes 56.4 Mbits/sec [ 4] 1.0- 2.0 sec 6.55 MBytes 54.9 Mbits/sec [ 4] 2.0- 3.0 sec 6.61 MBytes 55.5 Mbits/sec [ 4] 3.0- 4.0 sec 6.56 MBytes 55.0 Mbits/sec [ 4] 4.0- 5.0 sec 6.60 MBytes 55.4 Mbits/sec [ 4] 5.0- 6.0 sec 6.55 MBytes 55.0 Mbits/sec [ 4] 0.0- 6.0 sec 39.6 MBytes 55.3 Mbits/sec [ 4] Sent 28250 datagrams [ 4] Server Report: [ 4] 0.0- 6.0 sec 39.6 MBytes 55.2 Mbits/sec 0.613 ms 0/28249 (0%) [ 4] 0.0- 6.0 sec 1 datagrams received out-of-order [ 3] local 10.0.0.1 port 5001 connected with 10.0.0.2 port 34528 [ 3] 0.0- 1.0 sec 7.94 MBytes 66.6 Mbits/sec 0.249 ms 0/ 5661 (0%) [ 3] 1.0- 2.0 sec 7.89 MBytes 66.2 Mbits/sec 0.103 ms 0/ 5629 (0%) [ 3] 2.0- 3.0 sec 7.87 MBytes 66.0 Mbits/sec 0.135 ms 0/ 5613 (0%) [ 3] 3.0- 4.0 sec 7.86 MBytes 65.9 Mbits/sec 0.060 ms 0/ 5607 (0%) [ 3] 4.0- 5.0 sec 7.92 MBytes 66.5 Mbits/sec 0.084 ms 0/ 5652 (0%) [ 3] 5.0- 6.0 sec 7.98 MBytes 67.0 Mbits/sec 0.173 ms 0/ 5695 (0%) [ 3] 0.0- 6.0 sec 47.6 MBytes 66.4 Mbits/sec 0.114 ms 0/33921 (0%) [ 3] 0.0- 6.0 sec 1 datagrams received out-of-order Thanks in advance and best regards, -- Javier Martínez Canillas (+34) 682 39 81 69 Barcelona, Spain -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
