libusb performance on 8.1
doconnor at gsoft.com.au
Fri Jan 28 01:45:01 UTC 2011
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 aborted.
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
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