On 20.12.2007 13:25, Alan Stern wrote: > On Thu, 20 Dec 2007, Matthias Schniedermeyer wrote: > > > On 20.12.2007 11:42, Alan Stern wrote: > > > On Thu, 20 Dec 2007, Matthias Schniedermeyer wrote: > > > > > > > This is interesting, i pluged the (High-Speed-)HUB with the Low-Speed > > > > peripherals into another root-port. How can it be that this brings down > > > > the WHOLE usb subsystem, the computer that i replaced with this machine > > > > only had an USB-OHCI controller onboard, so i plugged the HDD into an > > > > add-on USB-controller and the same(!) low-speed devices where driven by > > > > the OHCI-driver? > > > > > > It doesn't bring down the whole USB subsystem. You are overreacting to > > > the volume of messages in the system log. All that went down was the > > > high-speed hub -- but of course when the hub went down it took along > > > the various devices plugged into it. > > > > The HDD isn't connected to an (addional) Hub, only the low-speed > > devices. And the low-speed devices are only present and not in "active" > > use while i copy something to the HDD. > > > > So can i assume that you suggest i should try some other hub for my > > low-speed devices? > > It's worth a try. For instance, a full-speed (USB 1.1) hub wouldn't > have these problems. > > Here's another idea: You can force your current hub to run at full > speed instead of high speed. You won't lose any performance, because > the devices attached to the hub don't run at high speed anyway. The > advantage is that when you do this, the hub will be on a different bus > from the disk drive. There shouldn't be any interference between them. > > As I recall from your logs, the hub is attached to port 4 on bus 7. > To force it into full speed, all you have to do is: > > echo 4 >/sys/class/usb_host/usb_host7/companion > > Unfortunately this setting will go away every time you reboot, so you > would need to add it to a startup script.
I did what you suggested and with this workaround applied i could copy 7GB without incident. So i presume the Hub for my low-speed-devices to be low-quality/faulty. I can live with this workaround. When i get my fingers on another usb-hub i can retest this, but for the time beeing i consider the matter closed. :-) Thank you all for the help. Bis denn -- Real Programmers consider "what you see is what you get" to be just as bad a concept in Text Editors as it is in women. No, the Real Programmer wants a "you asked for it, you got it" text editor -- complicated, cryptic, powerful, unforgiving, dangerous. - To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
