On Tue, 11 Aug 2009, cihan öztürk wrote: > 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.. It is possible for usbmon to lose events. You can tell if this happens because the Bs file (where B is the bus number) contains a count of lost events. Oddly, this fact doesn't seem to be mentioned explicitly in Documentation/usb/usbmon.txt. 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
