[Tfug] Crappy USB LVM/Software RAID10 performance?

[Jeff Breadner]

Bowie J. Poag wrote:
>
> dmesg shows that both drives are recognized as USB 2.0 devices, so it 
> isn't a legacy 1.x->2.0 USB problem..
> I have no other traffic moving over the pipe besides keyboard and 
> mouse, so I/O shouldn't be a problem.
> This box isn't doing anything else.
>
> So where's the crappy performance stemming from?
>
dmesg might see this as being a USB 2.0 _compatible_ device, but if you 
have it plugged into a USB hub with any USB 1.1 device (you mentioned a 
keyboard and mouse), then the hub's connection will drop down to USB 1.1 
speeds.

Try bypassing the USB hub or plugging only USB 2.0 devices into it, and 
see if your throughput improves, if only as a test. 

cheers
  Jeff