Re: MAX_USBFS_BUFFER_SIZE

[Pete Zaitcev]

On Wed, 1 Mar 2006 22:42:35 +0100, Renà Rebe <rene@xxxxxxxxxxxx> wrote:

> > > drivers/usb/core/devio.c:86
> > > #define MAX_USBFS_BUFFER_SIZE   16384

> So, queing alot URBs is the recommended way to sustain the bus? Allowing
> way bigger buffers will not be realistic?

Have you ever considered how many TDs have to be allocated to transfer
a data buffer this big? No, seriously. If your application cannot deliver
the tranfer speeds with 16KB URBs, we ought to consider if the combination
of our USB stack, usbfs, libusb and the application ought to get serious
performance enhancing surgery. The problem is obviously in the software
overhead.

-- Pete
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