[Tfug] Crappy USB LVM/Software RAID10 performance?

[Bowie J. Poag]

Hmmmmmm.. I didn't know that (that USB1.1 devices force USB 2.0 hubs to 
downshift..)

I suspect this might be the problem.

Cheers,
Bowie



Jeff Breadner wrote:
> 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
>
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