Thank you very much for advising the tool usbmon. I have implemented a parser that converts its outputs to the format suitable, to our requirements, and it all helped us very much for analysing the USB traffic. We realized that connecting two devices doesn't increase the throughput to the numbers I have mentioned before. I think we lose most of the packets that we thought were transferred, actually that's what usbmon outputs. Anyway, I will write a more detailed explanation when we complete our tests. I just wonder if usbmon is a tool that successfully captures ALL USB traffic between the custom usb driver and the host controller driver, along the bus we are sniffing. Can we trust the results of usbmon without doubt? I want to make sure about this because we will base tha analysis of our studies on this tool if we can trust its outputs are completely full, without any packets missing.. On Thu, Jul 16, 2009 at 5:02 PM, Alan Stern<stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Thu, 16 Jul 2009, cihan öztürk wrote: > >> The only problem remaining is we still cannot figure out why >> connecting two devices to the port pair drived by same HC >> lets us use 4.32Mbps per device(which is the expected case), but >> using only one of the devices for communication reduces the bandwidth >> to 1.72Mpbs, as I explained the calculations in my previous messages. > > This is where usbmon comes in handy. > > Alan Stern > > -- 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
