usb_interrupt_read speed different on USB 2 vs 3 port.

[Hans Petter Selasky]

On 01/03/14 13:59, Lundberg, Johannes wrote:
> Hi
> 
> I had a bug driving me crazy and I finally discovered something weird that
> was the reason.
> 
> I have a pair of AR glasses from Vuzix which have a
> gyro/accelerometer/compass which I read from USB using usb_interrupt_read
> (reading 42 bytes of data).
> 
> On my laptop I have two USB 2 and one USB 3 port.
> 
>>From the USB 2 port things behave normally and reading takes a millisecond
> or so.
> 
>>From the USB 3 port things get weird and the call to usb_interrupt_read
> takes over 20 milliseconds. I have been running this device on the same
> laptop for some time and haven't noticed this behavior before.
> 
> Can it be something that has been introduced recently or perhaps only my
> system is behaving weird?...
> 
> # uname -a
> FreeBSD PC 10.0-BETA1 FreeBSD 10.0-BETA1 #0: Sun Dec  8 16:15:23 JST
> 2013     root at PC:/usr/obj/usr/src/sys/GENERIC  i386
> 
> Best regards
> --
> Johannes Lundberg
> 

Hi,

Can you show output from
"usbconfig -d X.Y dump_device_desc dump_curr_config_desc"

In both cases?

--HPS