On 23/01/2011, at 24:03, Hans Petter Selasky wrote:
> You need to change the way you buffer the data. FreeBSD does not queue more 
> than 2 URB's at any time, and the turnaround time varies from 1ms to 125us 
> due 
> to hardware IRQ restrictions. Linux queues up all it can get, which leads to 
> other kind of problems. The current internal buffer limit is 16Kbyte 8000 
> times per second which gives a MAX of 128 MByte/second.

How difficult would it be to increase this? I obviously don't need any more 
throughput, however my application is very sensitive to latency, as I am 
reading out of a fairly small FIFO and if it fills up my entire run has to be 

Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
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