usb2 bulk read optimization ?
Thierry Herbelot
thierry.herbelot at free.fr
Fri Nov 28 07:07:20 PST 2008
Hello,
another day, another question :
I'm done converting an old "userland driver" to usb2 and libusb20 - and it
works ! (using the libusb API, for the time being).
The application is a data capture from a bulk endpoint, and I can't get more
than around 8 Mbps. The data are formatted as URBs of 40 kbytes.
This may be expected, as the machine is an oldish Pentium-III, with an
additional Acer-based USB-2 extension card.
(still, I have recompiled the -current kernel without the INVARIANTS and
WITNESS options)
I have had a quick look at the code of libusb20 and tried an increase of
bufsize in usb_get_transfer_by_ep_no, but with no discernable improvements.
Any idea ?
thanks
TfH
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