Slooooow USB key speeds

[Kanwar Ranbir Sandhu]

On Wed, 2009-01-28 at 17:19 -0600, Mikkel L. Ellertson wrote:
> You may want to take a look at /var/log/messages after plugging the
> USB key in and see what speed the USB key is talking at. 

Seems to me the kernel is detecting the USB key correctly and as a USB
2.0 device:

kernel: usb 1-5: new high speed USB device using ehci_hcd and address 5
kernel: usb 1-5: configuration #1 chosen from 1 choice
kernel: scsi11 : SCSI emulation for USB Mass Storage devices
kernel: usb 1-5: New USB device found, idVendor=13fe, idProduct=1f00
kernel: usb 1-5: New USB device strings: Mfr=1, Product=2,
SerialNumber=3
kernel: usb 1-5: Product: DataTraveler 2.0
kernel: usb 1-5: Manufacturer: Kingston
kernel: usb 1-5: SerialNumber: 5B850800007E
kernel: scsi 11:0:0:0: Direct-Access     Kingston DataTraveler 2.0 PMAP
PQ: 0 ANSI: 0 CCS
kernel: sd 11:0:0:0: [sdd] 15671296 512-byte hardware sectors (8024 MB)
kernel: sd 11:0:0:0: [sdd] Write Protect is off
kernel: sd 11:0:0:0: [sdd] Assuming drive cache: write through
kernel: sd 11:0:0:0: [sdd] 15671296 512-byte hardware sectors (8024 MB)
kernel: sd 11:0:0:0: [sdd] Write Protect is off
kernel: sd 11:0:0:0: [sdd] Assuming drive cache: write through
kernel: sdd: sdd1
kernel: sd 11:0:0:0: [sdd] Attached SCSI removable disk
kernel: sd 11:0:0:0: Attached scsi generic sg4 type 0

> You may
> want to look at /proc/bus/usb/devices to check the same thing.

And I see the speed as "480" here too:

T:  Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=480 MxCh= 6


I'm starting to think something is not quite right with the USB key (or
in the way it's being detected): I tested transferring files to my PSP,
but didn't see any of the same speed issues. I was able to copy large
files back and forth without any problems.

I should also add that after retesting the key with my HP laptop running
Fedora 10, the max speed I saw was 8 MBps.  The transfers would start
off in the 20+ MBps range, and then drop down to 8 MBps.  That's faster
than my desktop, but it's still dismal performance.

I need to try the stick on a Windows machine next.  I'm hoping I can
eliminate the USB key as the source of the problem.

Regards,

Ranbir

-- 
Kanwar Ranbir Sandhu
Linux 2.6.27.12-170.2.5.fc10.x86_64 x86_64 GNU/Linux 
17:58:50 up 3 days, 19:10, 2 users, load average: 0.12, 0.15, 0.15