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    SubjectRe: MAX_USBFS_BUFFER_SIZE
    On Thu, Mar 02, 2006 at 05:03:26PM +0100, Ren? Rebe wrote:
    > Hi,
    >
    > On Wednesday 01 March 2006 22:54, Greg KH wrote:
    >
    > > > > Why not just send down 2 urbs with that size then, that would keep the
    > > > > pipe quite full.
    > > >
    > > > Because that requires even more modifications to libusb and sane (i_usb) ...
    > >
    > > No, do it in your application I mean.
    >
    > Ok, tweaking libusb to queue N URBs for reads to be split (resulting in 9 URBs
    > in my usecase) I see a nearly 100% improvement here (2 times faster).
    >
    > How many URBs may I queue? Nearly infinite (in my case that would be max 64)
    > or is there some tiny static list somewhere in the affected code-path?

    There is no static list that I know of, as it is all just pointers.
    Just don't DOS the kernel by sending it an infinate ammount of memory :)

    More details can be found on the linux-usb-devel list if you ask there.

    thanks,

    greg k-h
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