The ugen driver isn't really made for good throughput.
Maybe you want to rool your own driver.

	-- Lennart

Berndt Josef Wulf wrote:
> On Mon, 14 Feb 2005 02:19 am, Jon Buller wrote:
> 
>>On 00 Jan 00 00:00:00,
>>
>>Berndt Josef Wulf wrote:
>>
>>>G'day,
>>>
>>>Where can I find benchtests performed for USB2 compliant controllers on
>>>NetBSD-i386 that would give some indication on the expected maximum data
>>>bandwidth? Currently, I'm only managing a maximum of 4MBytes/sec with a
>>>Intel 82801DB USB EHCI Controller (rev. 0x01) connected to a Cypress
>>>7C63013 device (FX2), which is a long way off from its theoratical
>>>480Mbits/sec of a fullspeed USB2 interface.
>>
>>You meant high-speed USB interface, didn't you?  Full-speed is
>>10Mbits/sec (or is it 12?)  High-speed is the fast one.  I (and
>>everyone else I know) thinks the USB people were on crack when they
>>thought up those names.  If you really are configuring it at full speed,
>>there is some chance for improvement there (2x or 3x), but not 100x.
> 
> 
> The measured data bandwidth is 4MBytes/sec. This is only 10% of the maximum 
> bandwidth theoretically achievable. Linux developers report data bandwidth of 
> 32-40MBytes/sec under the same conditions. 
> 
> Is there generic support for asynchronous reading and writing?  That
> is, multiple reads and writes outstanding, which notifies
> their completion? (Signals, polling, etc).
> 
> Is there a USB specific ioctl that allows submission of an USB "URB"
> (USB Request Block) asynchronously?
> 
> Is there a way of improving data throughput on this device or is this the best 
> we currently can do? Find below some kernel and userland messages on system 
> configuration and performance.
> 
> ./program_and_start.sh
> Using device /dev/ugen0 on bus /dev/usb3 vendor id 0xfffe product id 0x0002
> Read 102400000 bytes in 25 seconds and 1068 microseconds. Rate of 4095825 
> bytes/second
> 
>  ehci0 at pci0 dev 29 function 7: Intel 82801DB USB EHCI Controller (rev. 
> 0x01)
>  ehci0: interrupting at irq 11
>  ehci0: EHCI version 1.0
>  ehci0: companion controllers, 2 ports each: uhci0 uhci1 uhci2
>  usb3 at ehci0: USB revision 2.0
>  uhub3 at usb3
>  uhub3: Intel EHCI root hub, class 9/0, rev 2.00/1.00, addr 1
>  uhub3: single transaction translator
>  uhub3: 6 ports with 6 removable, self powered
> 
> usbdevs -v
> [,,,]
> Controller /dev/usb3:
> addr 1: high speed, self powered, config 1, EHCI root hub(0x0000), 
> Intel(0x8086), rev 1.00
>  port 1 addr 2: high speed, self powered, config 1, USRP Rev 2(0x0002), Free 
> Software Folks(0xfffe), rev 1.02
>  port 2 powered
>  port 3 powered
>  port 4 powered
>  port 5 powered
>  port 6 powered
> 
>