is my usb device connected to a fast port?

bartman
2008-05-10

I started a transfer last night to copy a 700M file to my USB key. It’s still going. I figured that it might have been OHCI vs EHCI issue. I had to remind myself how to check.

USB debug info is relayed via /proc/bus/usb/devices so you have to mount /proc/bus/usb like this:

    $ sudo mount -t usbfs none /proc/bus/usb

or put this in your /etc/fstab:

    none  /proc/bus/usb  usbfs  defaults  0  0

First off, lsusb was of no use. I couldn’t grok the output. Then I found this page: Linux and USB 2.0, where I found usbtree.

    $ usbtree
    /: Bus 05.Port 1: Dev 1, Class=root_hub, Drv=uhci_hcd/2p, 12M
    /: Bus 04.Port 1: Dev 1, Class=root_hub, Drv=uhci_hcd/2p, 12M
        |_ Port 2: Dev 2, If 0, Prod=Biometric Coprocessor, Class=vend., Drv=none, 12M
    /: Bus 03.Port 1: Dev 1, Class=root_hub, Drv=uhci_hcd/2p, 12M
        |_ Port 2: Dev 2, If 0, Prod=Generic USB Hub, Class=hub, Drv=hub/3p, 12M
            |_ Port 1: Dev 3, If 0, Prod=PFU-65 USB Keyboard, Class=HID, Drv=usbhid, 12M
            |_ Port 2: Dev 4, If 0, Prod=Trackball, Class=HID, Drv=usbhid, 1.5M
    /: Bus 02.Port 1: Dev 1, Class=root_hub, Drv=uhci_hcd/2p, 12M
    /: Bus 01.Port 1: Dev 1, Class=root_hub, Drv=ehci_hcd/8p, 480M
        |_ Port 3: Dev 4, If 0, Prod=RALLY2, Class=stor., Drv=usb-storage, 480M

Which does not explain my slow transfer rate… but it shows that my RALLY2 usb key has lots of bandwidth.

Update: I figured it out. I am using usbmount and the sync mount option was making writes extremely slow. After mounting it manually it was fine. Now I have to figure out if I want the comfort of usbmount or fast writes…

Tags:

Usb
Linux